Display device, electronic device, and system

ABSTRACT

A display region of an electronic device is enlarged. Alternatively, a display region of an electronic device is protected. Alternatively, a display device for extending a display region is provided. A system includes an electronic device including a first display portion positioned on a first surface including an upper surface of a housing and a second display portion positioned on a second surface including a first side surface of the housing, and a display device including a third display portion positioned on a third surface of a support portion and a connection portion having a function of connecting with the housing and a function of reversibly changing the relative positions of the support portion and the housing between a first configuration and a second configuration. The first configuration is a configuration in which the support portion covers the first display portion such that the second display portion is visible. The second configuration is a configuration in which the support portion and the housing are opened such that the first display portion, the second display portion, and the third display portion are visible.

TECHNICAL FIELD

One embodiment of the present invention relates to a display device. Oneembodiment of the present invention relates to an electronic device. Oneembodiment of the present invention relates to a system including adisplay device.

Note that one embodiment of the present invention is not limited to theabove technical field. As the technical field of one embodiment of thepresent invention disclosed in this specification, a semiconductordevice, a display device, a light-emitting device, a power storagedevice, a memory device, an electronic device, a lighting device, aninput device, an input/output device, a driving method thereof, or amanufacturing method thereof can be given as an example.

BACKGROUND ART

Electronic devices including display devices have recently beendiversified. As one of such electronic devices, an electronic devicesuch as a cellular phone, a smartphone, a tablet terminal, or a wearableterminal is given.

As display devices, typically, a light-emitting device including alight-emitting element such as an organic EL (Electro Luminescence)element or a light-emitting diode (LED: Light Emitting Diode), a liquidcrystal display device, electronic paper that performs display by anelectrophoretic method or the like, and the like are given.

Patent Document 1 discloses a flexible light-emitting device using anorganic EL element.

PRIOR ART DOCUMENT Patent Document

[Patent Document 1] Japanese Published Patent Application No.2014-197522

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

In recent years, browsability of display has been considered to beimproved by enlarging display regions of electronic devices to increasethe amount of display. However, in applications of portable devices andthe like, an enlargement of display regions might entail a reduction inportability (also referred to as portability). For this reason, animprovement in browsability of display and a high portability have beendifficult to achieve at the same time.

An object of one embodiment of the present invention is to enlarge adisplay region of an electronic device. Alternatively, an object is toprotect a display region of an electronic device. Alternatively, anobject is to provide a function of selecting the size of a displayregion of an electronic device depending on its application.Alternatively, an object is to provide a display device for extending adisplay region of an electronic device. Alternatively, an object is toprovide a highly portable electronic device.

Alternatively, an object of one embodiment of the present invention isto provide a novel display device, a novel electronic device, or a novelsystem including a display device.

Note that the description of these objects does not disturb theexistence of other objects. In one embodiment of the present invention,there is no need to achieve all of these objects. In addition, objectsother than the above can be derived from the description of thespecification and like.

Means for Solving the Problems

One embodiment of the present invention is a display device that isattachable to an electronic device. The electronic device includes ahousing, and the housing includes a first display portion and a seconddisplay portion. The first display portion is positioned on a firstsurface including an upper surface of the housing, and the seconddisplay portion is positioned on a second surface including a first sidesurface of the housing. In addition, the display device includes asupport portion, a connection portion, and a third display portion. Thethird display portion is positioned on a third surface of the supportportion. The connection portion has a function of connecting with thehousing and a function of reversibly changing the relative positions ofthe support portion and the housing between a first configuration and asecond configuration. The first configuration is a configuration inwhich the support portion covers the first display portion such that thesecond display portion is visible. The second configuration is aconfiguration in which the support portion and the housing are openedsuch that the first display portion, the second display portion, and thethird display portion are visible.

In addition, it is preferable that, in the first configuration, thefirst display portion and the third display portion be positioned toface each other.

In addition, it is preferable that, in the first configuration, thesupport portion be positioned not to cover at least a portion of thesecond display portion.

In addition, it is preferable that the support portion include alight-transmitting portion, and in the first configuration, thelight-transmitting portion be positioned to cover a portion of the firstside surface of the housing so as to overlap with the second displayportion.

In addition, it is preferable that the support portion be flexible andhave a function of allowing the third display portion to be bent.

In addition, it is preferable that the connection portion be flexible.In that case, it is preferable that the relative positions of thesupport portion and the housing be reversibly changed between the firstconfiguration and the second configuration by bending the connectionportion.

In addition, it is preferable that the connection portion include ahinge structure with two or more rotation axes. In that case, it ispreferable that the hinge structure enable the relative positions of thesupport portion and the housing to be reversibly changed between thefirst configuration and the second configuration.

In addition, it is preferable that the connection portion include areception portion supplied with power and a signal from the housing. Inthat case, it is preferable that the reception portion be supplied withthe power and the signal from the housing wirelessly.

In addition, it is preferable that the connection portion have afunction of being magnetically attachable to and detachable from thehousing.

In addition, another embodiment of the present invention is anelectronic device to which a display device is attachable. Theelectronic device includes a housing, and the housing includes a firstdisplay portion and a second display portion. The first display portionis positioned on a first surface including an upper surface of thehousing, and the second display portion is positioned on a secondsurface including a first side surface of the housing. In addition, thedisplay device includes a support portion, a connection portion, and athird display portion. The third display portion is positioned on athird surface of the support portion. The connection portion has afunction of connecting with the housing and a function of reversiblychanging the relative positions of the support portion and the housingbetween a first configuration and a second configuration. The firstconfiguration is a configuration in which the support portion covers thefirst display portion such that the second display portion is visible.The second configuration is a configuration in which the support portionand the housing are opened such that the first display portion, thesecond display portion, and the third display portion are visible.

In addition, it is preferable that the connection portion be attachableto a second side surface opposite to the first side surface of thehousing.

In addition, it is preferable that the first display portion and thesecond display portion be constituted by one display panel. In addition,it is preferable that the second display portion include a curvedportion.

In addition, it is preferable that the housing include a supportmechanism. In addition, it is preferable that, in the secondconfiguration, the support mechanism have a function of supporting thesupport portion such that the first surface and the third surface are ata predetermined angle.

In addition, it is preferable that the support mechanism include a lockmechanism such that the relative positions of the housing and thesupport portion include a plurality of stable positions.

In addition, it is preferable that the housing include a transmissionportion for supplying power and a signal to the connection portion. Inaddition, in that case, it is preferable that the transmission portionsupply the power and the signal from the housing wirelessly.

In addition, it is preferable that the housing have a function of beingmagnetically attachable to and detachable from the connection portion.

In addition, as another embodiment of the present invention, a systemincluding any of the above display devices and any of the aboveelectronic devices can be constituted.

Effect of the Invention

According to one embodiment of the present invention, a display regionof an electronic device can be enlarged. Alternatively, a display regionof an electronic device can be protected. Alternatively, a function ofselecting the size of a display region of an electronic device dependingon its application can be provided. Alternatively, a display device forextending a display region of an electronic device can be provided.Alternatively, a highly portable electronic device can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 A structure example of a system according to an embodiment.

FIG. 2 A structure example of a system according to an embodiment.

FIG. 3 A structure example of a system according to an embodiment.

FIG. 4 A structure example of a system according to an embodiment.

FIG. 5 A structure example of a system according to an embodiment.

FIG. 6 A structure example of a system according to an embodiment.

FIG. 7 A structure example of a system according to an embodiment.

FIG. 8 A structure example of a system according to an embodiment.

FIG. 9 A structure example of a system according to an embodiment.

FIG. 10 A structure example of a system according to an embodiment.

FIG. 11 A structure example of a system according to an embodiment.

FIG. 12 A structure example of a system according to an embodiment.

FIG. 13 A structure example of a system according to an embodiment.

FIG. 14 A structure example of a system according to an embodiment.

FIG. 15 A structure example of a system according to an embodiment.

FIG. 16 A structure example of a system according to an embodiment.

FIG. 17 A structure example of a system according to an embodiment.

FIG. 18 A structure example of a system according to an embodiment.

FIG. 19 A structure example of a system according to an embodiment.

FIG. 20 A structure example of a system according to an embodiment.

FIG. 21 A structure example of an input device of according to anembodiment.

FIG. 22 A structure example of an input device of according to anembodiment.

FIG. 23 A structure example of an input device of according to anembodiment.

FIG. 24 A structure example of an input device of according to anembodiment.

FIG. 25 A structure example of an input/output device according to anembodiment.

FIG. 26 A structure example of an input/output device according to anembodiment.

FIG. 27 A structure example of an input/output device according to anembodiment.

FIG. 28 A structure example of an input/output device according to anembodiment.

FIG. 29 A structure example of an input/output device according to anembodiment.

FIG. 30 A structure example of an input/output device according to anembodiment.

FIG. 31 A structure example of an input/output device according to anembodiment.

FIG. 32 A structure example of an input/output device according to anembodiment.

FIG. 33 A structure example of an input/output device according to anembodiment.

FIG. 34 A structure example of an input/output device according to anembodiment.

FIG. 35 A structure example of an input/output device according to anembodiment.

FIG. 36 A structure example of an input/output device according to anembodiment.

FIG. 37 A structure example of an input/output device according to anembodiment.

FIG. 38 A structure example of an input/output device according to anembodiment.

FIG. 39 A structure example of an input/output device according to anembodiment.

FIG. 40 A structure example of an input/output device according to anembodiment.

FIG. 41 A structure example of an input/output device according to anembodiment.

FIG. 42 A structure example of an input/output device according to anembodiment.

FIG. 43 A structure example of an input/output device according to anembodiment.

FIG. 44 Drawings illustrating a pixel provided with a touch sensoraccording to an embodiment.

FIG. 45 Drawings illustrating an operation of a touch sensor and a pixelaccording to an embodiment.

MODE FOR CARRYING OUT THE INVENTION

Embodiments will be described in detail with reference to the drawings.Note that the present invention is not limited to the followingdescription. It will be readily appreciated by those skilled in the artthat modes and details thereof can be modified in various ways withoutdeparting from the spirit and scope of the present invention. Thus, thepresent invention should not be construed as being limited to what isdescribed in the following embodiments.

Note that in the structures of the invention described below, the sameportions or portions having similar functions are denoted by the samereference numerals in different drawings, and a repeated descriptionthereof is omitted. Furthermore, the same hatching pattern is applied tosimilar functions, and the portions are not especially denoted byreference numerals in some cases.

Note that in each drawing described in this specification, the size, thelayer thickness, or the region of each component is exaggerated forclarity in some cases. Therefore, it is not necessarily limited to theillustrated scale.

Note that in this specification and the like, ordinal numbers such as“first” and “second” are used in order to avoid confusion betweencomponents and do not limit the number.

Embodiment 1

In this embodiment, structure examples of a display device, anelectronic device, and a system of one embodiment of the presentinvention will be described.

Structure Example 1

FIGS. 1(A1), (B1), and (C1) are perspective schematic views of a system10 including a display device 11 and an electronic device 21. FIG. 1(A1)illustrates a state where the display device 11 and the electronicdevice 21 overlap with each other (this state is also referred to as aclosed state or a folded state). FIG. 1(B1) illustrates a state wherethey are unfolded (this state is also referred to as an opened state).FIG. 1(C1) illustrates a state where they are further unfolded (opened)to be substantially parallel to each other.

In addition, FIGS. 1(A2) and (A3) are cross-sectional schematic viewscorresponding to the section line A1-A2 and the section line A3-A4 inFIG. 1(A1), respectively. In addition, FIG. 1(B2) is a cross-sectionalschematic view corresponding to the section line A5-A6 in FIG. 1(B1). Inaddition, FIG. 1(C2) is a cross-sectional schematic view correspondingto the section line A7-A8 in FIG. 1(C1). Note that the internalstructure of a housing 22 is omitted in each cross-sectional schematicview.

The display device 11 includes a support 12, a display portion 13, and aconnection portion 14. The electronic device 21 includes the housing 22,a display portion 23, and a display portion 24.

The connection portion 14 connects the support 12 and the housing 22 toeach other. In addition, the connection portion 14 has a function ofchanging the relative positions of the support 12 and the housing 22.This enables the relative positions of the support 12 and the housing 22to be reversibly changed from a configuration illustrated in FIG. 1(A1)to a configuration illustrated in FIG. 1(C1) through a configurationillustrated in FIG. 1(B1).

For example, the connection portion 14 may be flexible or may have ahinge structure. A structure example of the connection portion 14 havinga hinge structure will be described later.

In addition, the connection portion 14 can be attached to the housing22. Here, the connection portion 14 and the housing 22 may be attachedand fixed to each other so that a user cannot detach them, or theconnection portion 14 and the housing 22 may be attached to each otherso that a user can detach them. For example, a portion of the housing 22may have a fixing mechanism with which the connection portion 14 canengage, or may have a fixing mechanism with which the housing 22 and theconnection portion 14 can be mechanically or magnetically fixed to eachother so as to be detachable as described later. In addition, in thatcase, it is preferable that the connection portion 14 and the housing 22be electrically connected to each other or be capable of transmittingand receiving power and a signal therebetween.

The display portion 13 is provided along a surface of the support 12.More specifically, the display portion 13 is provided along a surface ofthe support 12 which is positioned on the electronic device 21 side in astate where the support 12 and the electronic device 21 overlap witheach other as illustrated in FIG. 1(A1).

The electronic device 21 includes, inside the housing 22, a battery, aprinted board on which a variety of ICs such as an arithmetic unit and adriver circuit are mounted, and the like. In addition, electroniccomponents such as a wireless receiver, a wireless transmitter, awireless power receiver, and a variety of sensors, e.g., an accelerationsensor, may be incorporated as appropriate into the housing 22, so thatthe electronic device 21 can function as a portable terminal, a portableimage reproducing device, a portable lighting device, or the like. Acamera, a speaker, a variety of input/output terminals such as aterminal for power supply and a terminal for signal supply, a variety ofsensors such as an optical sensor, an operation button, or the like mayalso be incorporated into the housing 22. In addition, the support 12may also include a printed board, an electronic component, a camera, aspeaker, a variety of input/output terminals such as a terminal forpower supply and a terminal for signal supply, a variety of sensors suchas an optical sensor, an operation button, or the like as describedabove.

The display portion 23 is provided along a surface of the housing 22. Inaddition, the display portion 24 is provided along a side surface of thehousing 22.

An example in which the display portion 23 and the display portion 24are connected seamlessly is described here. For example, the displayportion 23 and the display portion 24 may be formed by curving orbending a portion of one display panel. In FIGS. 1(B1), (C1), and thelike, a boundary between the display portion 23 and the display portion24 is indicated by a broken line.

It is preferable that the display portion 23 perform display along aflat surface. It is also preferable that at least a portion of thedisplay portion 24 perform display along a curved surface.

Here, when the display portion 23 and the display portion 24 areseamlessly continuous, for example, there is a case where the boundarytherebetween is unclear. In this specification and the like, when thetwo display portions are seamlessly continuous, a line connecting pointsof change in curvature of these surfaces in the direction from thedisplay portion 23 side toward the display portion 24 side is regardedas the boundary between the two display portions. Therefore, when thetwo display portions are seamlessly continuous, at least a portion ofthe display portion 24 includes a curved surface.

In the configuration in which the support 12 and the housing 22 overlapwith each other (this configuration is also referred to as a closedstate) as illustrated in FIG. 1(A1) or the like, the display portion 23is preferably covered with the support 12. In this way, a portion of thesupport 12 functions as a protective cover for a surface of the displayportion 23 and can prevent the surface of the display portion 23 frombeing damaged. In addition, the support 12 can prevent a surface of thedisplay portion 13 from being damaged at this time. In addition, in thestate illustrated in FIG. 1(A1), the surface of the display portion 23and the surface of the display portion 13 may be in contact with eachother. However, a gap is preferably provided between the surface of thedisplay portion 13 and the surface of the display portion 23 such thatthese surfaces are not in contact with each other, in which case thesesurfaces can be prevented from being rubbed together and damaged.

Furthermore, in that case, the display portion 24 is preferably notcovered with the support 12. In this way, the display portion 24 isvisible to a user even in the state where the support 12 and the housing22 are closed; thus, the user can see information displayed on thedisplay portion 24. Furthermore, when the display portion 24 includes atouch sensor, an icon or the like displayed on the display portion 24can be operated.

As the information displayed on the display portion 24, variousinformation such as notification of an incoming e-mail, call, socialnetworking service (SNS), or the like, the subject of an e-mail, an SNS,or the like, the sender of an e-mail, an SNS, or the like, the message,the date, the time, information on playing voice or music, the volume,the temperature, the battery level, the communication status, thereception strength of an antenna, and the status of downloading a filecan be displayed. In addition, the display portion 24 may display iconsassociated with various applications, icons associated with variousfunctions, operation buttons, a slider, or the like. For example, thereis an icon associated with a function of adjusting the volume orfast-forwarding, a fast-rewinding, and the like during the playback ofvoice or music. Alternatively, an icon associated with a function ofanswering the call or placing the call on hold or a function of awakingthe operation invalid state (the lock state) of the electronic device 20or the system 10, for example, may be displayed.

In addition, in the state where the support 12 and the housing 22 areclosed, it is preferable that the display portion 23 and the displayportion 13 not perform display. It is preferable that pixels in aportion of the display panel not be driven in the case where the displayportion 23 and the display portion 24 include a single display panel. Inaddition, in the case where a display device including a backlight likea transmissive liquid crystal device is used as the display portion 23or the display portion 13, it is preferable that the backlight not bedriven.

Power consumption can be significantly reduced by preventing a portionof the display portion that is not visible to a user from displaying animage (or from operating) when the support 12 and the housing 22 areclosed.

In the configuration illustrated in FIG. 1(B1), the display portion 23can display an image functioning as a keyboard or a touch pad, forexample. That is, when a portion of the display portion 23 functions asan input means and the display portion 13 functions as a main displayportion (main display), the system 10 can be used as a notebook-typecomputer or a game machine. Alternatively, when both the display portion13 and the display portion 23 display text data, the system 10 can beused as a foldable electronic book reader.

In the configuration illustrated in FIG. 1(C1), the display portion 13can function as an extended display. That is, the display portion 23 andthe display portion 13 can display a large image that the electronicdevice 21 alone cannot display, or can separately display differentimages. Furthermore, the electronic device 21 and the display device 11can separately display images associated with different applications toachieve multitasking.

In addition, FIGS. 2(A1) and (A2) illustrate an example of the casewhere the display device 11 is folded to the side opposite to thedisplay portion 23 side of the housing 22 (hereinafter also referred toas the back side or back surface side). FIG. 2(A1) illustrates thedisplay portion 23 side, and FIG. 2(A2) illustrates the back side of thehousing 22. In addition, FIG. 2(A3) illustrates a cross-sectionalschematic view corresponding to the section line A9-A10 in FIG. 2(A1).

In such a configuration, display can be performed along two surfaces orthree surfaces of the housing 22. For example, when the display portion23 and the display portion 13 display the same image, a user can showthe same image as that the user sees to a person facing the user.Alternatively, when the display portion 23 and the display portion 13display different images, different images can be presented to a userand a person facing the user, which can be utilized for an applicationsuch as an interactive game.

Note that the above usage methods are mere examples, and images or thelike that can be displayed on the display portions in each configurationare not limited to those given above. A variety of display for differentapplications can be performed.

FIG. 3 illustrates an example of the case where the support 12 of thedisplay device 11 is bent. In that case, the display portion 13 of thedisplay device 11 can perform display along the curved surface.

In addition, FIG. 1(A2) and the like illustrate the case where a sidesurface of the housing 22 on a side to which the connection portion 14is attached has a convexly curved shape. Furthermore, the connectionportion 14 and the housing 22 are attached to each other such that theconnection portion 14 curves along the curved surface in theconfiguration in which the support 12 and the housing 22 overlap witheach other. This structure can prevent the relative positions of thesupport 12 and the housing 22 from being easily changed when the support12 and the housing 22 overlap with each other. In addition, when thesupport 12 and the housing 22 are closed, two side surfaces of thesystem 10, i.e., a side surface on the display portion 24 side and aside surface on the connection portion 14 side, may be similarly curvedand have substantially symmetrical shapes as illustrated in FIGS. 1(A2)and (A3). In this way, the system 10 with the display device 11 attachedthereto can have a plainer (or simpler) design. In addition, it ispreferable that a surface of the housing 22 have a recessed shape intowhich the connection portion 14 fits so as not to generate a leveldifference between the surface of the connection portion 14 and thesurface of the housing 22 in the state where the support 12 and thehousing 22 overlap with each other.

In addition, the side surface of the housing 22 on the side to which theconnection portion 14 is attached may have a flat shape as illustratedin FIGS. 4(A1), (A2), (B1), and (B2). In that case, the connectionportion 14 includes a portion that is bent along the surface of thehousing 22 in the configuration in which the housing 22 and the support12 overlap with each other as illustrated in FIGS. 4(A1) and (A2). Inaddition, a connecting portion between the housing 22 and the connectionportion 14 (here, an end portion of the connection portion 14) may bepositioned on the display portion 23 side with respect to the backsurface of the housing 22; in this way, a design can be made in whichthe height of the display portion 23 and the height of the displayportion 13 are substantially equal to each other in the state where thehousing 22 and the support 12 are opened as illustrated in FIG. 4(B2).

Here, it is preferable that modules including a touch sensor be providedin the display panels in the display portion 13, the display portion 23,and the display portion 24 so as to overlap with the display surfacesides of the display panels. In addition, at least a portion of themodule including a touch sensor in the display portion 24 or the displayportion 13 is preferably flexible and bendable along the display panel.At this time, the module including a touch sensor may be bonded to thedisplay panel with an adhesive or the like, or a polarizing plate or acushion material (e.g., a separator) may be provided therebetween. Inaddition, the thickness of the module including a touch sensor ispreferably smaller than or equal to that of the display panel.

Alternatively, the display panels in the display portion 13, the displayportion 23, and the display portion 24 may function as a touch panel.For example, the display panel may be an on-cell touch panel or anin-cell touch panel. In the case of using the structure of the on-cellor in-cell touch panel, the thickness of the display panel can be smalleven when the display panel also serves as a touch panel.

In addition, the display portion 13 does not necessarily have a functionof a touch sensor. Even in that case, the display device 11 can functionas an extended display of the electronic device 21 to improve displaybrowsability. In addition, the display portion 13 preferably has afunction of a touch sensor because a region that a user can operate canbe enlarged and therefore a more user-friendly application can beincorporated.

As materials that can be used for the housing 22, plastic, a metal suchas aluminum, an alloy such as stainless steel or a titanium alloy,rubber such as silicone rubber, and the like can be used.

In the case where the connection portion 14 is flexible, a material thatpartly or entirely changes its shape elastically can be favorably used.For example, the whole connection portion 14 may be elastic, or theconnection portion 14 may contain an elastic material at least in abending portion.

For example, a material with a Young's modulus lower than that of thehousing 22 can be used for the connection portion 14. In addition, evenin the case where a material with a Young's modulus higher than orcomparable to that of the housing 22 is used, the material can be usedfor the connection portion 14 by making the connection portion 14thinner than the housing 22. As materials that can be used to form theconnection portion 14, plastic, rubber, a metal, an alloy, and the likecan be used. For example, a material such as a silicone resin or a gelmay also be used.

In the case where a hinge is used as the connection portion 14, a rigidmaterial is preferably used for that part. For example, plastic, a metalsuch as aluminum, an alloy such as stainless steel or a titanium alloy,or the like is preferably used.

It is preferable to use a highly rigid material for the support 12because a function of a protective cover can be enhanced. It is alsopreferable to use an elastic material for the support 12 because animpact can be relieved when the system 10 is dropped or the system 10comes in contact with a hard object, for example. In addition, when thesupport 12 and the display panel used for the display portion 13 areeach flexible, the display portion 13 can perform display along a curvedsurface. A material that can be used for the support 12 can be selectedas appropriate from materials that can be used for the housing 22 or theconnection portion 14.

A variety of display panels can be used as the display portion 13, thedisplay portion 23, and the display portion 24.

In addition, in the case where the display portion 13 and the support 12are used in a bent state, a flexible display panel is preferably used inthe display portion 13. Furthermore, even in the case where the displayportion 13 and the support 12 are not used in a bent state, the displaydevice 11 can include a flexible display panel to reduce the weight ofthe display device 11. Accordingly, an increase in total weight of thesystem 10 can be suppressed even when the display device 11 is used.

Here, in the case where the display portion 24 performs display along acurved surface, a flexible display panel is preferably used in thedisplay portion 24. In addition, a structure is preferable in which asingle flexible display panel be used in the display portion 23 and thedisplay portion 24 and be partly curved in the display portion 24.Accordingly, the number of components of the electronic device 21 can bereduced, or the weight of the electronic device 21 can be decreased withthe use of the flexible display panel.

In addition, as display panels or touch panels used in the displayportion 23, the display portion 24, and the display portion 13, the samedisplay elements or different display elements may be used. For example,a touch panel including a liquid crystal element may be used in thedisplay portion 23 and the display portion 24, and a touch panelincluding an organic EL element may be used in the display portion 13.Alternatively, a touch panel including a liquid crystal element may beused in the display portion 23, and a touch panel including an organicEL element may be used in the display portion 24 and the display portion13.

A display element which can be used in the display portion 13, thedisplay portion 23, and the display portion 24, a display device or adisplay panel, which is a device including a display element, alight-emitting element, and a light-emitting device, which is a deviceincluding a light-emitting element, can use various types or can includevarious elements.

For example, a display device including a display element such as a MEMS(Micro Electro Mechanical System) element or an electron-emissiveelement can be used. As a MEMS display element, a MEMS shutter displayelement, an optical interference type MEMS display element, and the likeare given. A carbon nanotube may be used for the electron-emissiveelement. Alternatively, electronic paper may be used. As the electronicpaper, an element using a microcapsule method, an electrophoreticmethod, an electrowetting method, an Electronic Liquid Powder(registered trademark) method, or the like can be used.

For example, in this specification and the like, an active matrix methodin which an active element is included in a pixel or a passive matrixmethod in which an active element is not included in a pixel can beused.

In an active matrix method, as an active element (an active element or anon-linear element), not only a transistor but also various activeelements (active elements or non-linear elements) can be used. Forexample, an MIM (Metal Insulator Metal), a TFD (Thin Film Diode), or thelike can also be used. Since such an element has few numbers ofmanufacturing steps, manufacturing cost can be reduced or yield can beimproved. Alternatively, since the size of such an element is small, theaperture ratio can be improved, so that power consumption can be reducedor higher luminance can be achieved.

As a method other than the active matrix method, the passive matrix typein which an active element (an active element or a non-linear element)is not used can also be used. Since an active element (an active elementor a non-linear element) is not used, the manufacturing process can besimplified, whereby manufacturing cost can be reduced or yield can beimproved. Alternatively, since an active element (an active element or anon-linear element) is not used, the aperture ratio can be improved, sothat power consumption can be reduced or higher luminance can beachieved, for example.

The above is the description of Structure Example 1.

Structure Example 2

A structure example whose structure is partly different from that ofStructure Example 1 described above will be described below. Note thatthe description of the portions already described is omitted anddifferent portions are described.

FIGS. 5(A1), (A2), (B), and (C) are perspective schematic views of asystem 10 described as an example below. The system 10 illustrated ineach drawing of FIG. 5 is different from that in Structure Example 1mainly in including a support mechanism 25.

FIGS. 5(A1) and (A2) illustrate a state where the housing 22 and thesupport 12 are closed. FIG. 5(A1) illustrates the support 12 side, andFIG. 5(A2) illustrates the back surface side of the housing 22.

The housing 22 includes the support mechanism 25 in part thereof. Asillustrated in FIGS. 5(A1, A2), the support mechanism 25 is preferablystored in the housing 22 when not in use. For example, a portion of asurface of the housing 22 and a portion of a surface of the supportmechanism 25 are made to be positioned on the same plane when thesupport mechanism 25 is stored in the housing 22. In this way, theelectronic device 21 can have a functionally excellent design and can beput in a bag or a pocket without getting stuck. In addition, when thehousing 22 and the support mechanism 25 are integrated as describedabove, the support mechanism 25 does not need to be carried aroundseparately from the electronic device 21, leading to improvedconvenience.

FIG. 5(B) illustrates a state where the support mechanism 25 is pulledout from the housing 22. In addition, FIG. 5(C) illustrates a statewhere the support 12 is further opened.

The support mechanism 25 has a function of supporting a portion of asurface of the support 12 on the side opposite to the display portion13. In other words, the support mechanism 25 has a function ofsupporting the support 12 such that a surface of the display portion 23of the electronic device 21 and a surface of the display portion 13 ofthe display device 11 are at a predetermined angle. The supportmechanism 25 described above can stabilize the position of the support12 as compared with the configuration illustrated in FIG. 1(B1) or FIG.3, for example. In addition, even when the connection portion 14 doesnot include a hinge mechanism, for example, the relative positions ofthe housing 22 and the support 12 can be fixed.

Here, the support mechanism 25 preferably includes a mechanism capableof locking the relative positions of the support 12 and the housing 22at one or more stable positions (this mechanism is also referred to as alock mechanism) and a mechanism capable of releasing the lock. It isparticularly preferable that the lock mechanism have two or more stablepositions. With such a mechanism, a user can adjust the angle accordingto his or her preference.

Note that the structure of the support mechanism 25 is not particularlylimited to the above as long as the mechanism can support the support12. For example, FIG. 6 illustrates an example of the structure of thesupport mechanism 25 capable of supporting one end portion of thesupport 12. With a mechanism of the support mechanism 25 to rotate withrespect to the housing 22, the support 12 can be supported in a statewhere the support 12 and the housing 22 are opened at a given angle.

The above is the description of Structure Example 2.

Structure Example 3

A structure example whose structure is partly different from those ofthe above structure examples will be described below. Note that thedescription of the portions already described is omitted and differentportions are described.

FIGS. 7(A), (B), and (C) are perspective schematic views of a system 10described as an example below. The system 10 illustrated in each drawingof FIG. 7 is different from those described above mainly in a structureof the connection portion 14.

FIG. 7(A) illustrates a state where the housing 22 and the support 12are closed. FIG. 7(B) illustrates a state where they are opened. Inaddition, FIG. 7(C) illustrates a state where the electronic device 21and the display device 11 are separated from each other.

The connection portion 14 of the display device 11 illustrated eachdrawing of in FIG. 7 includes a movable portion 14 a and a detachmentportion 14 b.

The movable portion 14 a has a function of connecting the detachmentportion 14 b and the support 12 to each other. The movable portion 14 aalso has a function of bending in a manner similar to that of theconnection portion 14 in the above structural example.

The housing 22 includes an engagement portion 26 which engages with thedetachment portion 14 b. Accordingly, the display device 11 can bedetachably attached to the electronic device 21. The engagement portion26 and the detachment portion 14 b may include a mechanism capable oflocking each other mechanically so that these components attached toeach other are not easily detached from each other.

In addition, the engagement portion 26 preferably includes a terminalfor transmitting power or a signal from the housing 22 to the displaydevice 11. In addition, the detachment portion 14 b preferably includesa terminal for receiving the signal. Moreover, the terminal of theengagement portion 26 and the terminal of the detachment portion 14 bcan be provided so as to be in contact with each other when the displaydevice 11 is attached to the electronic device 21.

Alternatively, the housing 22 may include an antenna for transmittingthe power or the signal in a position close to the engagement portion26, and the detachment portion 14 b may include an antenna for receivingthe power or the signal, in order to wirelessly supply the power or thesignal from the electronic device 21 to the display device 11.

Here, in the housing 22, the terminal for transmitting power or a signalor the antenna and a circuit for wirelessly transmitting them can bereferred to as a transmission portion. In addition, the terminalprovided in the connection portion 14 for receiving power or a signal orthe antenna and a circuit for wirelessly receiving them can be referredto as a reception portion.

In addition, FIG. 8 illustrates a configuration in which the housing 22includes a connection mechanism 27 and a terminal 28 instead of theengagement portion 26. Furthermore, the detachment portion 14 b includesa connection mechanism 15 and a terminal 16.

It is preferable here that the connection mechanism 27 and theconnection mechanism 15 be magnetically connectable to each other. Forexample, a magnet or the like may be provided in one of the connectionmechanism 27 and the connection mechanism 15, and a magnetic metal or asoft magnetic material that can be magnetized by the magnetic body canbe provided in the other. Alternatively, an electromagnet may be used.

In addition, the terminal 28 and the terminal 16 are electricallyconnected to each other when the detachment portion 14 b and the housing22 are connected to each other, and through these terminals, power or asignal can be transmitted and received between the housing 22 and thedisplay device 11. In addition, the terminal 28 and the terminal 16 mayhave a structure in which power or a signal can be transmitted andreceived through the above-described antennas.

The above is the description of Structure Example 3.

Structure Example 4

A structure example whose structure is partly different from those ofthe above structure examples will be described below. Note that thedescription of the portions already described is omitted and differentportions are described.

FIGS. 9(A), (B), and (C) are perspective schematic views of a system 10described as an example below. The system 10 illustrated in each drawingof FIG. 9 is different from those described above mainly in a structureof the support 12.

The support 12 includes a window portion 17 which transmits visiblelight. The window portion 17 is provided on the side opposite to theconnection portion 14 with the display portion 13 therebetween.

A portion provided with the window portion 17 in the support 12 isflexible. Accordingly, in the state where the housing 22 and the support12 are closed, a side surface of the housing 22 can be covered with thewindow portion 17 as illustrated in FIG. 9(B), from the stateillustrated in FIG. 9(A). Therefore, the window portion 17 can functionas a protective cover for protecting a surface of the display portion 24provided at the side surface of the housing 22.

Since the window portion 17 transmits visible light, a user can see thedisplay portion 24 even in the state where the side surface of thehousing 22 is covered with the window portion 17 as illustrated in FIG.9(B). In addition, in the case where the display portion 24 has afunction of a touch panel, a user can operate the display portion 24through the window portion 17.

A material of the window portion 17 is not particularly limited as longas the material transmits visible light and is flexible. For example, aresin, glass that is thin enough to have flexibility, or the like can beused. In the case of using a resin, a surface thereof is preferablysubjected to hard-coating treatment or the like because the surface canbe prevented from being damaged easily.

In addition, a light-transmitting display panel can also be used in thewindow portion 17. For example, a display panel having a see-throughfunction with a light-transmitting material used for a wiring of a pixelcan be used. This enables the window portion 17 to be used as a displayportion in a state where the housing 22 and the support 12 are opened asillustrated in FIG. 9(C), and thus enables a display region to beenlarged. In addition, the window portion 17 may have a function of atouch sensor.

In addition, the window portion 17 can protect the surface of thedisplay portion 24 by being bent along the display portion 24 also inthe case where the support 12 is located on the back surface side of thehousing 22.

FIGS. 10(A) and (B) illustrate a structure including a fastener 18 onthe side of the support 12 which is opposite to the connection portion14. FIG. 10(B) is a cross-sectional schematic view in a state where oneend of the support 12 is fixed to the housing 22 with the fastener 18.

The fastener 18 has, for example, an opening as illustrated in FIG.10(A). In addition, a projection 29 engaging with the opening of thefastener 18 is provided on the back surface side of the housing 22 asillustrated in FIG. 10(B). In this manner, the fastener can fix thesupport 12 and the housing 22 in a closed state.

Note that the structure of the fastener 18 is not limited to thisexample, and for example, the support 12 and the housing 22 may bemagnetically fastened to each other. In that case, the fastener 18 whichprojects from the support 12 as illustrated in FIG. 10(A) may beprovided, or overlapping portions of the support 12 and the housing 22may be magnetically fixed to each other so as to be detachable.

The above is the description of Structure Example 4.

Structure Example 5

A structure example whose structure is partly different from those ofthe above structure examples will be described below. Note that thedescription of the portions already described is omitted and differentportions are described.

FIGS. 11(A1), (A2), (B), and (C) are perspective schematic views of asystem 10 described as an example below. The system 10 illustrated ineach drawing of FIG. 11 is different from those described above mainlyin a structure of the connection portion 14.

The connection portion 14 includes a hinge 31 and an immovable portion32.

The immovable portion 32 has a function of connecting the hinge 31 andthe support 12 to each other. In the case where a flexible material isused for the support 12, a material that is more rigid than the support12 is preferably used for the immovable portion 32. In addition, in thecase where the support 12 has rigidity, a portion of the support 12 mayfunction as the immovable portion 32.

FIG. 11(A2) is an enlarged view of a region surrounded by a dasheddotted line in FIG. 11(A1). In FIG. 11(A2), the support 12 and thehousing 22 are illustrated as being transparent.

The hinge 31 includes a first portion 31 a and a second portion 31 b.The first portion 31 a and the housing 22 are attached to each other soas to be rotatable on a rotation axis 36. The first portion 31 a and thesecond portion 31 b are attached to each other so as to be rotatable ona rotation axis 37. The second portion 31 b and the immovable portion 32are attached to each other so as to be rotatable on a rotation axis 38.

Here, the rotation axis 36 and the rotation axis 37 are preferablyparallel to each other. In addition, the rotation axis 38 and therotation axis 37 are preferably perpendicular to each other.

Such a structure including the hinge 31 with two or more rotation axesas the connection portion 14 can improve the degree of freedom in termsof the relative positions of the housing 22 and the display device 11.

FIG. 11(B) illustrates an example in which the support 12 is rotatedwith respect to the housing 22 on the rotation axis 37 from the stateillustrated in FIG. 11(A1). The hinge 31 allows a reversible change inshape from the state in which the housing 22 and the support 12 areclosed to the state in which they are opened.

In addition, FIG. 11(C) illustrates an example in which the support 12is rotated on the rotation axis 38 from the state illustrated in FIG.11(B). In this manner, the hinge 31 enables the support 12 to be rotatednot only in a folding direction but also in a direction crossing thefolding direction, and enables the orientation of the support 12 to beadjusted according to user's preference.

In addition, FIG. 12(A) illustrates a state where the support 12 isrotated on the rotation axis 36 and the rotation axis 37 from the stateillustrated in FIG. 11(B) and the support 12 is positioned on the backsurface side of the housing 22.

In addition, FIG. 12(B) illustrates a state where the support 12 isrotated on the rotation axis 38 and is thereby positioned such that thedisplay portion 13 of the support 12 and the back surface of the housing22 face each other. In that case, the display portion 13 can beprotected by the support 12 even in the case where the support ispositioned on the back surface side of the housing 22.

Here, the connection portion 14 including the hinge 31 and the immovableportion 32 is preferably configured to enable power or a signal to betransmitted and received between the electronic device 21 and thedisplay device 11. For example, this can be achieved by providing awiring or the like inside the hinge 31. Alternatively, wireless power orsignal transmission and reception may be achieved by providing anantenna in the housing 22 and providing an antenna in the immovableportion 32 or the support 12.

Note that the hinge 31 and the immovable portion 32 are described aspart of the display device 11 in the system 10 described here as anexample, but can also be regarded as part of the electronic device 21.Alternatively, the system 10 can be regarded as including the displaydevice 11 that includes the support 12, the electronic device 21 thatincludes the housing 22, and a connection device that includes the hinge31.

The above is the description of Structure Example 5.

Modification Example

Modification examples in which the structure of the electronic device 21is partly different will be described below.

In each of the above-described structure examples, the side surface ofthe housing 22 of the electronic device 21 has a convexly curved surfaceand the display portion 24 is provided along the convexly curved surfaceand also on the back surface side of the housing 22. The structure ofthe display portion 24 is not limited thereto, and the display portion24 may be provided along a flat surface. Furthermore, the displayportion 24 is not necessarily provided also on the back surface side ofthe housing 22, and may have an end portion at a portion of the sidesurface of the housing 22.

FIGS. 13(A) and (B) illustrate an example of the case where a portion ofthe housing 22 in which the display portion 24 is provided has a flatsurface. In addition, the case where a plane parallel to the displayportion 23 and a plane parallel to a portion of the display portion 24are not parallel to each other is illustrated. In addition, the displayportion 23 and the display portion 24 are connected at the boundarytherebetween, and the display portion 23 and the display portion 24 canperform continuous display.

FIGS. 14(A) and (B) illustrate an example in which an end portion of thedisplay portion 24 is positioned at a portion of the side surface of thehousing 22 without reaching the back surface of the housing 22. Here, inthe example illustrated in FIG. 14, the display portion 24 can performdisplay along a curved surface.

In addition, in the above-described example, the display portion 23 andthe display portion 24 are seamlessly continuous. However, these displayportions are not necessarily continuous, and a non-display portion maybe provided between the two display portions.

FIG. 15(A) illustrates an example of the structure illustrated in eachdrawing of FIG. 1 in the case where the display portion 23 and thedisplay portion 24 are not continuous. Here, the display portion 23 andthe display portion 24 may include different display panels. Forexample, a display panel having low flexibility or no flexibility can beused in the display portion 23, and a display panel having higherflexibility than the display panel used in the display portion 23 can beused in the display portion 24.

In addition, FIG. 15(B) illustrates an example of the structureillustrated in FIG. 13 in the case where the display portion 23 and thedisplay portion 24 are not continuous. In the structure illustrated inFIG. 15(B), the display portion 23 and the display portion 24 can eachbe a display portion which performs display along a flat surface. Inthat case, a display panel having low flexibility or no flexibility canbe used in each of the display portion 23 and the display portion 24.

In addition, the display portion 24 can be variously configured as longas it covers a portion of the side surface of the housing 22.

FIG. 16(A) is a perspective view of the configuration illustrated inFIG. 1(B1) which is seen from the back surface side of the housing 22.As illustrated, the display portion 24 can be provided so as to reach aportion of the back surface of the housing 22. In addition, FIG. 16(B)illustrates an example of the case where the area of a portion of theback surface of the housing 22 covered with the display portion 24 islarge. FIG. 16(B) illustrates an example in which an end portion of thedisplay portion 24 is located closer to the connection portion 14 thanthe middle of the back surface of the housing 22.

In addition, although the display portion 24 is provided along the sidesurface in the direction of a long side of the housing 22 in theabove-described examples, the display portion 24 may be provided along aside surface in the direction of a short side of the housing 22 asillustrated in FIG. 17(A). Furthermore, the display portion 24 may beprovided along two or more side surfaces of the housing 22 asillustrated in FIG. 17(B).

In addition, although the connection portion 14 of the display device 11is attached in the direction of a long side of the housing 22 in theabove-described examples, the position at which the connection portion14 is attached is not limited. For example, the connection portion 14may be attached to a side surface in the direction of a short side ofthe housing 22 as illustrated in FIGS. 18(A) and (B). Here, FIG. 18(A)illustrates an example in which the display portion 24 is provided alonga side surface in the direction of a short side of the housing 22. Inaddition, FIG. 18(B) illustrates an example in which the display portion24 is provided along a side surface in the direction of a long side ofthe housing 22.

Note that it is needless to say that the structure of the display device11 in the system 10 described as a modification example is not limitedto the structure described here and can be replaced with any of thestructures described in the above structure examples. Furthermore, thestructure of the housing 22 can be changed as appropriate depending onthe structure of the connection portion 14 of the display device 11.

The above is the description of the modification example.

<Hardware Configuration Examples of System>

Hardware configuration examples of the electronic device 21 and thedisplay device 11 included in the system 10 will be described below withreference to the drawings.

FIG. 19 is a block diagram illustrating a configuration example of thesystem 10. The system 10 includes the display device 11 and theelectronic device 21.

Note that in a block diagram attached to this specification, componentsare classified according to their functions and shown as independentblocks; however, it is practically difficult to completely separate thecomponents according to their functions, and one component may have aplurality of functions.

The electronic device 21 includes an arithmetic portion (CPU) 50, amemory device 51, a tilt detection portion 52, a wireless communicationportion 53, an antenna 54, a power management portion 55, a powerreception portion 56, a battery module 57, a shape detection portion 58,an external interface 60, a camera module 61, a sound controller 62, anaudio output portion 63, an audio input portion 64, a sensor 65, a touchpanel 71, a display controller 72, a touch sensor controller 73, adisplay controller 82, a touch sensor controller 83, and the like.

In addition, the display device 11 includes a touch panel 81.

Note that the configurations of the system 10, the electronic device 21,and the display device 11 illustrated in FIG. 19 are mere examples, andnot all the components are necessarily included. The system 10, theelectronic device 21, and the display device 11 include necessarycomponents among the components illustrated in FIG. 19 and may include acomponent other than the components illustrated in FIG. 19.

The arithmetic portion 50 can function as a central processing unit(CPU: Central Processing Unit), and has a function of controllingcomponents such as the memory device 51, the tilt detection portion 52,the wireless communication portion 53, the power management portion 55,the shape detection portion 58, the external interface 60, the cameramodule 61, the sound controller 62, and the like, for example.

Signals may be transmitted between the arithmetic portion 50 and eachcomponent via a system bus (not illustrated). In addition, thearithmetic portion 50 can process signals input from each componentwhich is connected through the system bus and generate signals to beoutput to each component, so that each component connected to the systembus can be controlled comprehensively.

Note that a transistor which includes an oxide semiconductor in achannel formation region and achieves an extremely low off-state currentcan be used in the arithmetic portion 50. Since the transistor has anextremely low off-state current, with the use of the transistor as aswitch for holding electric charge (data) which flows into a capacitorserving as a memory element, a long data retention period can beensured. By utilizing this characteristic for a register or a cachememory of the arithmetic portion 50, normally off computing is achievedwhere the arithmetic portion 50 operates only when needed and data onthe previous processing is stored in the memory element in the rest oftime; thus, power consumption of the electronic device 21 can bereduced.

Another microprocessor such as a DSP (Digital Signal Processor) or a GPU(Graphics Processing Unit) can be used in addition to the CPU as thearithmetic portion 50. Furthermore, such a microprocessor may beobtained with a PLD (Programmable Logic Device) such as a FPGA (FieldProgrammable Gate Array) or a FPAA (Field Programmable Analog Array).The arithmetic portion 50 interprets and executes instructions fromvarious programs with the processor to process various kinds of data andcontrol programs. The programs executed by the processor may be storedin a memory region of the processor or may be stored in the memorydevice 51.

The arithmetic portion 50 may include a main memory. The main memory caninclude a volatile memory such as a RAM (Random Access Memory) or anonvolatile memory such as a ROM (Read Only Memory).

For example, a DRAM (Dynamic Random Access Memory) is used as the RAMincluded in the main memory, in which case a memory space as a workspacefor the arithmetic portion 50 is virtually allocated and used. Anoperating system, an application program, a program module, programdata, and the like which are stored in the memory device 51 are loadedinto the RAM to be executed. The data, program, and program module whichare loaded into the RAM are directly accessed and operated by thearithmetic portion 50. Moreover, characteristic data for calculating theposition of the electronic device 21 and the relative positionalrelationship between the electronic device 21 and the display device 11from the data input from the tilt detection portion 52 and the shapedetection portion 58 of the present invention may be read out from thememory device 51 as a lookup table and stored in the main memory.

On the other hand, in the ROM, a BIOS (Basic Input/Output System),firmware, or the like for which rewriting is not needed can be stored.As the ROM, a mask ROM, an OTPROM (One Time Programmable Read OnlyMemory), an EPROM (Erasable Programmable Read Only Memory), or the likecan be used. As the EPROM, a UV-EPROM (Ultra-Violet ErasableProgrammable Read Only Memory) which can erase stored data byirradiation with ultraviolet rays, an EEPROM (Electrically ErasableProgrammable Read Only Memory), a flash memory, and the like can begiven.

As the memory device 51, a memory media drive such as a hard disc drive(Hard Disc Drive: HDD) or a solid state drive (Solid State Drive: SSD);a memory device including a non-volatile memory element, such as a flashmemory, an MRAM (Magnetoresistive Random Access Memory), a PRAM (PhaseChange RAM), a ReRAM (Resistance RAM), or a FeRAM (Ferroelectric RAM); amemory device including a volatile memory element, such as a DRAM(Dinamic Ram) or an SRAM (Static RAM); or the like can be used.

In addition, as the memory device 51, a memory device which isattachable and detachable through the external interface 60 with aconnector, such as an HDD or an SSD; or a media drive of a memory mediumsuch as a flash memory, a Blu-ray disc, or a DVD can be used. Note thatthe memory device 51 is not necessarily incorporated in the electronicdevice 21, and a memory device outside the electronic device 21 may beused as the memory device 51. In that case, the memory device may beconnected through the external interface 60, or data transmission andreception may be wirelessly performed using the wireless communicationportion 53.

The tilt detection portion 52 has a function of detecting a tilt, aposture, and the like of the electronic device 21. For example, anacceleration sensor, an angular velocity sensor, a vibration sensor, apressure sensor, a gyroscope sensor, or the like can be used for thetilt detection portion 52. Alternatively, a plurality of these sensorsmay be combined.

The wireless communication portion 53 can communicate via the antenna54. For example, the wireless communication portion 53 controls acontrol signal for connecting the electronic device 21 to a computernetwork according to instructions from the arithmetic portion 50 andtransmits the signal to the computer network. Accordingly, communicationcan be performed by connecting the electronic device 21 to a computernetwork such as the Internet which is an infrastructure of the WorldWide Web (WWW), an intranet, an extranet, a PAN (Personal Area Network),a LAN (Local Area Network), a CAN (Campus Area Network), a MAN(Metropolitan Area Network), a WAN (Wide Area Network), or a GAN (GlobalArea Network). In addition, when a plurality of methods are used as itscommunication method, a plurality of antennas 54 may be includeddepending on the communication methods.

For example, a high frequency circuit (an RF circuit) may be included inthe wireless communication portion 53 for receiving and transmitting anRF signal. The high frequency circuit is a circuit for mutuallyconverting an electromagnetic signal into an electric signal in afrequency band set in accordance with different national laws andperforming wireless communication with another communication deviceusing the electromagnetic signal. Several tens of kilohertz to severaltens of gigahertz is a practical frequency band which is generally used.The high frequency circuit includes a high frequency circuit portion andan antenna which are compatible with a plurality of frequency bands; thehigh frequency circuit portion can include an amplifier (amplifier), amixer, a filter, a DSP, an RF transceiver, or the like. In the case ofperforming wireless communication, it is possible to use, as acommunication protocol or a communication technology, a communicationsstandard such as GSM (Global System for Mobile Communication: registeredtrademark), EDGE (Enhanced Data Rates for GSM Evolution), CDMA2000 (CodeDivision Multiple Access 2000), or W-CDMA (Wideband Code DivisionMultiple Access), or specifications with a communications standarddeveloped by IEEE such as Wi-Fi (Wireless Fidelity: registeredtrademark), Bluetooth (registered trademark), or ZigBee (registeredtrademark).

In the case of using the electronic device 21 as a telephone, thewireless communication portion 53 controls a connection signal forconnecting the electronic device 21 to the telephone line according toinstructions from the arithmetic portion 50 and transmits the signal tothe telephone line.

The power management portion 55 can manage a charge state of the batterymodule 57. In addition, the power management portion 55 supplies powerfrom the battery module 57 to each component. The power receptionportion 56 has a function of receiving power supplied from the outsideand charging the battery module 57. The power management portion 55 cancontrol the operation of the power reception portion 56 depending on thecharge state of the battery module 57.

The battery module 57 includes one or more primary batteries orsecondary batteries, for example. In addition, in the case of indoor useor the like, an alternate-current power source (AC) may be used as anexternal power source. Particularly in the case of using the electronicdevice 21 separately from the external power source, it is favorablethat the battery module 57 have a large charge/discharge capacity whichallows the electronic device 21 to be used for a long time. The batterymodule 57 may be charged using a battery charger separated from theelectronic device 21. At this time, charging may be performed throughwires using an AC adaptor; alternatively, charging may be performed by awireless power feeding method such as an electric field coupling method,an electromagnetic induction method, or an electromagnetic resonance(electromagnetic resonant coupling) method. As the secondary batterywhich can be used for the battery module 57, for example, a lithium ionsecondary battery, a lithium ion polymer secondary battery, or the likecan be given.

The power management portion 55 may include a battery management unit(BMU), for example. The BMU collects data on cell voltage or celltemperatures of the battery, monitors overcharge and overdischarge,controls a cell balancer, handles a deterioration state of the battery,calculates the remaining battery power (State Of Charge: SOC), andcontrols detection of a failure, etc.

The power management portion 55 controls power transmission from thebattery module 57 to each component through the system bus or otherpower supply lines. The power management portion 55 can include a powerconverter with a plurality of channels, an inverter, a protectioncircuit, and the like, for example.

In addition, the power management portion 55 preferably has a functionof reducing power consumption. As the function of reducing powerconsumption, the following can be given: after detection of no input tothe electronic device 21 for a given period, the power managementportion 55 lowers the clock frequency of the arithmetic portion 50 orstops input of clocks of the arithmetic portion 50, stops operation ofthe arithmetic portion 50 itself, or stops operation of an auxiliarymemory, thereby controlling power supply to each component and reducingpower consumption. Such a function is performed with the powermanagement portion 55 alone or interlocking with the arithmetic portion50.

The shape detection portion 58 has a function of detecting the relativepositional relationship between the display device 11 and the electronicdevice 21 and outputting the data to the arithmetic portion 50 via thesystem bus. In addition, in the case where the display device 11 and theelectronic device 21 are detachable from each other, the shape detectionportion 58 may have a function of detecting data on whether or not thedisplay device 11 is connected to the electronic device 21 andoutputting the data to the arithmetic portion 50.

As the shape detection portion 58, a sensor similar to that in the tiltdetection portion 52 can be provided in the display device 11. When dataon the posture of the display device 11 is input from the shapedetection portion 58 to the arithmetic portion 50 via the system bus,the arithmetic portion 50 can calculate the relative positionalrelationship between the electronic device 21 and the display device 11from the data on the posture of the electronic device 21 detected by thetilt detection portion 52 and the data on the posture of the displaydevice 11.

Alternatively, a sensor for detecting the curved shape of the connectionportion 14 can be used as the shape detection portion 58. When such asensor is used, a plurality of acceleration sensors or the like may beprovided in, for example, the connection portion 14 so that thearithmetic portion 50 can calculate the shape of the connection portion14 from change in acceleration at each position. Alternatively, a sensorincluding a piezoelectric element may be provided in the connectionportion 14 so that bending can be detected. Alternatively, a sensorwhose physical characteristics (resistivity, thermal conductivity, andtransmissivity) change with a curving may be incorporated in theconnection portion 14 so that the shape of the connection portion 14 canbe calculated from change in the physical characteristics.

In addition, in the case where a hinge is included as the connectionportion 14, the rotation angle of the hinge on each rotation axis can bedetected mechanically, optically, or electromagnetically.

In addition, the shape detection portion 58 may have a function ofdetecting two states, a state where the electronic device 21 and thedisplay device 11 are closed and a state where they are opened. As anexample of an optical detection method, for example, a light-receivingelement may be provided on the surface of the housing 22 or the surfaceof the support 12, and blocking of external light when they are closedmay be utilized for detection. Alternatively, a light-receiving elementmay be provided on one of the surface of the housing 22 and the surfaceof the support 12, a light source may be provided on the other, andincidence of light from the light source on the light-receiving elementwhen they are closed may be utilized for detection. In that case, it ispreferable to use infrared light as light from the light source becauseusers cannot recognize it.

Note that the structure of the shape detection portion 58 is not limitedto the above and any of a variety of sensors to which, for example, amechanical, electromagnetic, thermal, acoustic, or chemical means isapplied can be used as long as the sensor can detect the relativepositional relationship between the electronic device 21 and the displaydevice 11.

Note that the shape detection portion 58 is included in the electronicdevice 21 in the example illustrated in FIG. 19. However, in some cases,the display device 11 may include the shape detection portion 58, or aportion of the shape detection portion 58 may be included in theelectronic device 21, and the other portion thereof may be included inthe display device 11.

As the external interface 60, for example, one or more buttons orswitches (also referred to as housing switches), an external port towhich another input component can be connected, and the like which areprovided on the housing can be given. The external interface 60 isconnected to the arithmetic portion 50 via the system bus. As thehousing switches, a switch associated with power on/off, a button foradjusting the volume, a camera shooting button, and the like may beincluded.

In addition, for example, the external port of the external interface 60can be connected to an external device such as a computer or a printerthrough a cable. Typically, a USB (Universal Serial Bus) terminal or thelike is given. In addition, as the external port, a LAN (Local AreaNetwork) connection terminal, a digital broadcasting reception terminal,an AC adaptor connection terminal, or the like may be provided. Inaddition, a transceiver for optical communication, without limitation towire communication, using infrared rays, visible light, ultravioletrays, or the like, may be provided.

The camera module 61 is connected to the arithmetic portion 50 via thesystem bus. For example, a still image or a moving image can be taken insynchronization with pushing a housing switch or touch operation of thetouch panel 71 or the touch panel 81.

The audio output portion 63 includes a speaker, an audio outputconnector, or the like, for example. In addition, the audio inputportion 64 includes a microphone, an audio input connector, or the like,for example. The audio input portion 64 is connected to the soundcontroller 62, and is connected to the arithmetic portion 50 via thesystem bus. Audio data input to the audio input portion 64 is convertedinto a digital signal in the sound controller 62 and then processed inthe sound controller 62 and the arithmetic portion 50. Meanwhile, thesound controller 62 generates an analog audio signal audible to a useraccording to instructions from the arithmetic portion 50 and outputs theanalog audio signal to the audio output portion 63. To the audio outputconnector of the audio output portion 63, an audio output device such asheadphones or a headset can be connected and a sound generated in thesound controller 62 is output to the device.

The sensor 65 includes a sensor unit and a sensor controller. The sensorcontroller supplies electric power from the battery module 57 to thesensor. Moreover, the sensor controller converts the input from thesensor into a control signal and outputs it to the arithmetic portion 50via the system bus. The sensor controller may handle errors made by thesensor or may calibrate the sensor. Note that the sensor controller mayinclude a plurality of controllers which control the sensor.

The sensor 65 may include any of a variety of sensors which measureforce, displacement, position, speed, acceleration, angular velocity,rotational frequency, distance, light, liquid, magnetism, temperature, achemical substance, a sound, time, hardness, electric field, current,voltage, electric power, radiation, flow rate, humidity, gradient,oscillation, smell, and infrared rays.

The touch panel 71 is connected to the display controller 72 and thetouch sensor controller 73. The display controller 72 and the touchsensor controller 73 are each connected to the arithmetic portion 50 viathe system bus.

The display controller 72 controls the touch panel 71 according todrawing instructions input from the arithmetic portion 50 via the systembus so that a predetermined image is displayed on the display surface ofthe touch panel 71.

The touch sensor controller 73 controls a touch sensor of the touchpanel 71 according to requests from the arithmetic portion 50 via thesystem bus. In addition, the touch sensor controller 73 outputs a signalreceived by the touch sensor to the arithmetic portion 50 via the systembus. Note that the function of calculating touch position data from asignal received by the touch sensor may be given to the touch sensorcontroller 73 or the data may be calculated by the arithmetic portion50.

The touch panel 81 of the display device 11 can be connected to thedisplay controller 82 and the touch sensor controller 83 when thedisplay device 11 is attached to the electronic device 21. Like thedisplay controller 72 and the touch sensor controller 73, the displaycontroller 82 and the touch sensor controller 83 can control the touchpanel 81.

Here, the touch panel 81 and the display controller 82 or the touchsensor controller 83 may be connected to each other through a cable or awiring or may transmit and receive signals wirelessly.

In addition, although not illustrated here, power may be supplied to thedisplay device 11 from the power management portion 55 of the electronicdevice 21. In that case, a power supply line for supplying power by wireor wirelessly from the power management portion 55 to the display device11 (or the touch panel 81) can be used.

Note that the display controller 82 and the touch sensor controller 83are included in the electronic device 21 here, but may be included inthe display device 11. In that case, the display controller 82 and thetouch sensor controller 83 can be connected by wire or wirelessly to thearithmetic portion 50 through the system bus of the electronic device21.

In addition, the display controller 72 may also serve as the displaycontroller 82, and similarly, the touch sensor controller 73 may alsoserve as the touch sensor controller 83. That is, the display controller72 and the touch sensor controller 73 may control both the touch panel71 and the touch panel 81.

It is preferable that the display device 11 include minimum componentssuch as the touch panel 81 and the electronic device 21 include theother components as illustrated in FIG. 19 because the configuration ofthe display device 11 can be simplified. Accordingly, the display device11 can be lightweight and compact. This makes it possible to minimizethe total weight and an increase in thickness of the system 10 includingthe electronic device 21 and the display device 11. It is alsopreferable that components originally included in the electronic device21 be used as components for driving the display device 11, such as thedisplay controller 82 and the touch sensor controller 83, because no newcomponents, or only minimum components, need to be added to theelectronic device 21 to obtain the system 10.

FIG. 20 illustrates an example in which the display device 11 includesthe battery module 85.

The battery module 85 can be connected to the power management portion55 of the electronic device 21 when the display device 11 is attached tothe electronic device 21. The power management portion 55 can controlthe battery module 85 in addition to the battery module 57. It is alsopreferable that power be supplied to the battery module 85 from thepower reception portion 56 through the power management portion 55 sothat the battery module 85 can be charged.

Note that the display device 11 may include a power management portionand a power reception portion in the case where the display device 11 isdetachable. Accordingly, the battery module 85 can be charged in thedisplay device 11 alone.

The battery module 85 is preferably positioned so as to overlap with thetouch panel 81. In that case, when the support 12 and the touch panel 81of the display device 11 are flexible and can be used in a bent state,it is preferable that the battery module 85 be also at least partlyflexible. As the secondary battery which can be used for the batterymodule 85, for example, a lithium ion secondary battery, a lithium ionpolymer secondary battery, and the like are given. It is also preferablethat a laminate pouch be used as an external package of the battery sothat the battery has flexibility.

A film used for the laminate pouch is a single-layer film selected froma metal film (aluminum, stainless steel, nickel steel, and the like), aplastic film made of an organic material, a hybrid material filmincluding an organic material (an organic resin, fiber, or the like) andan inorganic material (ceramic or the like), and a carbon-containinginorganic film (a carbon film, a graphite film, or the like); or astacked-layer film including a plurality of the above films. A metalfilm can easily be embossed. Forming depressions or projections byembossing increases the surface area of the film exposed to outside air,achieving an efficient heat dissipation effect.

In particular, by using a laminate pouch including a metal film havingdepressions and projections by embossing as a laminate pouch, a straincaused by stress applied to the laminate pouch can be relieved, leadingto an effective decrease of defects such as a break of the laminatepouch due to bending of a secondary battery.

Note that the configuration examples are described here in which thedisplay device 11 includes the touch panel 81 or includes the touchpanel 81 and the battery module 85, but the display device 11 mayinclude other components. For example, the display device 11 may includeone or more of the above-described components of the electronic device21 or may include another or other components. In one example, thedisplay device 11 may include the touch panel 81, the battery module 85,a power management portion, and a power reception portion. In anotherexample, the display device 11 may include the touch panel 81, thebattery module 85, a power management portion, a power receptionportion, an arithmetic portion, and a camera module.

The above is the description of system hardware configurations.

At least part of this embodiment can be implemented in combination withany of the other embodiments described in this specification asappropriate.

Embodiment 2

In this embodiment, structure examples of an input/output device (atouch panel), an input device (a touch sensor), an output device (adisplay panel), and the like which can be used for the display portionof the above embodiment will be described.

Structure Example of Sensor Electrode or the Like

A structure example of the input device (touch sensor) will be describedbelow with reference to the drawings.

FIG. 21(A) is a schematic top view of an input device 310. The inputdevice 310 includes a plurality of electrodes 331, a plurality ofelectrodes 332, a plurality of wirings 341, and a plurality of wirings342 over a substrate 330. In addition, the substrate 330 is providedwith an FPC (Flexible Printed Circuit) 350 which is electricallyconnected to each of the plurality of wirings 341 and the plurality ofwirings 342. FIG. 21(A) also illustrates an example in which the FPC 350is provided with an IC 351.

FIG. 21(B) shows an enlarged view of a region surrounded by a dasheddotted line in FIG. 21(A). The electrodes 331 are each in the form of arow of a plurality of rhombic electrode patterns arranged in a lateraldirection of this figure. The rhombic electrode patterns aligned in aline are electrically connected to each other. The electrodes 332 arealso each in the form of a row of a plurality of rhombic electrodepatterns arranged in a longitudinal direction of this figure, and therhombic electrode patterns aligned in a line are electrically connectedto each other. In addition, part of the electrode 331 and part of theelectrode 332 overlap and intersect with each other. At thisintersection portion, an insulator is sandwiched in order to avoid anelectrical short-circuit (short-circuit) between the electrode 331 andthe electrode 332.

In addition, as illustrated in FIG. 21(C), the electrodes 332 mayinclude a plurality of rhombic electrodes 333 and bridge electrodes 334.The island-shaped electrodes 333 are arranged in the longitudinaldirection of the figure, and two adjacent electrodes 333 areelectrically connected to each other by the bridge electrode 334. Such astructure makes it possible that the electrodes 333 and the electrodes331 can be formed at the same time by processing the same conductivefilm. This can prevent variations in the thickness of these films, andcan prevent the resistance value and the light transmittance of eachelectrode from varying from place to place. Note that although theelectrodes 332 include the bridge electrodes 334 here, the electrodes331 may have such a structure.

In addition, as illustrated in FIG. 21(D), a shape in which rhombicelectrode patterns of the electrodes 331 and the electrodes 332illustrated in FIG. 21(B) are hollowed out and only edge portions areleft may be used. In that case, when the widths of the electrodes 331and the electrodes 332 are small enough to be invisible to the users,the electrodes 331 and the electrodes 332 can be formed using alight-blocking material such as a metal or an alloy, as will bedescribed later. In addition, either the electrodes 331 or theelectrodes 332 illustrated in FIG. 21(D) may include the above bridgeelectrodes 334.

One of the electrodes 331 is electrically connected to one of thewirings 341. In addition, one of the electrodes 332 is electricallyconnected to one of the wirings 342. Here, either one of the electrodes331 and the electrodes 332 corresponds to a row wiring, and the othercorresponds to a column wiring.

The IC 351 has a function of driving the touch sensor. A signal outputfrom the IC 351 is supplied to either of the electrodes 331 and theelectrodes 332 through the wiring 341 or the wiring 342. In addition, acurrent (or a potential) flowing to either of the electrodes 331 and theelectrodes 332 is input to the IC 351 through the wiring 341 or thewiring 342.

When a touch panel is formed in such a manner that the input device 310overlaps with a display screen of the display panel, alight-transmitting conductive material is preferably used for theelectrodes 331 and the electrodes 332. In addition, in the case where alight-transmitting conductive material is used for the electrodes 331and the electrodes 332 and light from the display panel is extractedthrough the electrodes 331 or the electrodes 332, it is preferable thata conductive film containing the same conductive material be placedbetween the electrodes 331 and the electrodes 332 as a dummy pattern. Inthis manner, part of a space between the electrodes 331 and theelectrodes 332 is filled with the dummy pattern, which can reducevariation in light transmittance. As a result, unevenness in luminanceof light transmitted through the input device 310 can be reduced.

As a light-transmitting conductive material, a conductive oxide such asindium oxide, indium tin oxide, indium zinc oxide, zinc oxide, or zincoxide to which gallium is added can be used. Note that a film includinggraphene can be used as well. The film including graphene can be formed,for example, by reducing a film containing graphene oxide formed in afilm shape. As a reducing method, a method with application of heat orthe like can be given.

Furthermore, a metal or an alloy which is thin enough to have alight-transmitting property can be used. For example, a metal such asgold, silver, platinum, magnesium, nickel, tungsten, chromium,molybdenum, iron, cobalt, copper, palladium, or titanium, or an alloycontaining any of these metals can be used. Alternatively, a nitride ofthe metal or the alloy (e.g., titanium nitride), or the like may beused. Alternatively, a stacked film in which two or more of conductivefilms containing the above materials are stacked may be used.

In addition, for the electrodes 331 and the electrodes 332, a conductivefilm that is processed to be thin enough to be invisible to the usersmay be used. Such a conductive film is processed into a lattice shape (amesh shape), for example, which makes it possible to achieve both highconductivity and high visibility of the display device. In that case, itis preferable that the conductive film have a portion in which the widthis greater than or equal to 30 nm and less than or equal to 100 μm,preferably greater than or equal to 50 nm and less than or equal to 50μm, more preferably greater than or equal to 50 nm and less than orequal to 20 μm. In particular, the conductive film having a patternwidth of 10 μm or less is preferable because it is extremely difficultto see by the users.

As examples, enlarged schematic views of part of the electrodes 331 (aregion surrounded by a dashed-dotted line in FIG. 21(B)) are shown inFIGS. 22(A) to (D). FIG. 22(A) illustrates an example of the case wherea lattice-shaped conductive film 361 is used. At this time, theconductive film 361 is preferably placed so as not to overlap with thedisplay element included in the display device so that light from thedisplay device is not blocked. In that case, it is preferable that thedirection of the lattice be provided so as to be the same as thedirection of the display element arrangement and that the pitch of thelattice be an integer multiple of the pitch of the display elementarrangement.

In addition, FIG. 22(B) illustrates an example of a lattice-shapedconductive film 362, which is processed so as to be provided withtriangle openings. Such a structure makes it possible to further reducethe resistance compared with the case illustrated in FIG. 22(A).

In addition, a conductive film 363, which has an irregular patternshape, may be used as illustrated in FIG. 22(C). Such a structure canprevent generation of moire when overlapping with the display portion ofthe display device.

In addition, conductive nanowires may be used for the electrodes 331 andthe electrodes 332. FIG. 22(D) illustrates an example in which nanowires364 are used. The nanowires 364 are dispersed at appropriate density soas to be in contact with the adjacent nanowires, which can form atwo-dimensional network; therefore, the nanowires 364 can function as aconductive film with an extremely high light-transmitting property. Forexample, a nanowire which has a mean value of the diameters of greaterthan or equal to 1 nm and less than or equal to 100 nm, preferablygreater than or equal to 5 nm and less than or equal to 50 nm, morepreferably greater than or equal to 5 nm and less than or equal to 25 nmcan be used. As the nanowire 364, a metal nanowire such as an Agnanowire, a Cu nanowire, or an Al nanowire, a carbon nanotube, or thelike can be used. In the case of using an Ag nanowire, for example, alight transmittance of 89% or more and a sheet resistance of 40ohms/square or more and 100 ohms/square or less can be achieved.

Although examples in which a plurality of rhombuses are aligned in onedirection are shown in FIG. 21(A) and the like as top surface shapes ofthe electrodes 331 and the electrodes 332, the shapes of the electrodes331 and the electrodes 332 are not limited thereto and can have varioustop surface shapes such as a belt shape (a rectangular shape), a beltshape having a curve, and a zigzag shape. In addition, although theabove shows the electrodes 331 and the electrodes 332 arranged to beperpendicular to each other, they are not necessarily arranged to beperpendicular and the angle formed by the two electrodes may be lessthan 90°.

FIGS. 23(A) to (C) illustrate examples of the case where electrodes 336and electrodes 337, which have a top surface shape of thin lines, areused instead of the electrodes 331 and the electrodes 332. FIG. 23(A)shows an example in which the linear electrodes 336 and electrodes 337are arranged so as to form a lattice shape.

In addition, FIG. 23(B) shows an example in which the electrodes 336 andthe electrodes 337 have a top surface shape of a zigzag shape. In thatcase, as shown in FIG. 23(B), the electrodes 336 and the electrodes 337are preferably arranged such that the centers of their straight-lineportions do not overlap with each other but are relatively displacedfrom each other. This enables a longer length of a portion where theelectrodes 336 and the electrodes 337 face parallel to each other. Thisis preferable because the capacitance between the electrodes can beincreased and the sensitivity can be increased. Alternatively, as shownin FIG. 23(C), a shape in which part of the straight-line portion of azigzag shape is projected is used as a top surface shape of theelectrodes 336 and the electrodes 337, which can increase thecapacitance between the electrodes because the length of the partsfacing each other can be longer even when the centers of thestraight-line portions overlap with each other.

FIGS. 24(A), (B), and (C) show enlarged views of a region surrounded bya dashed dotted line in FIG. 23(B), and FIGS. 24(D), (E), and (F) showenlarged views of a region surrounded by a dashed dotted line in FIG.23(C). In addition, in these drawings, the electrodes 336, theelectrodes 337, and intersection portions 338 at which the electrodes336 and the electrodes 337 intersect are illustrated. The straight-lineportions of the electrodes 336 and the electrodes 337 shown in FIGS.24(A) and (D) may have a serpentine shape that meanders with angledcorners as shown in FIGS. 24(B) and (E) or may have a serpentine shapein which a curve continuously meanders as shown in FIGS. 24(C) and (F).

The above is the description of the electrode shapes or the like.

Structure Example of Touch Panel

A structure example of a touch panel will be described below withreference to the drawings as an example of an input/output deviceincluding the input device of one embodiment of the present invention.

Structure Example

FIG. 25(A) is a schematic perspective view of a touch panel 100. Inaddition, FIG. 25(B) is a developed schematic perspective view of FIG.25(A). Note that only typical components are illustrated for simplicity.In addition, in FIG. 25(B), some components (such as the substrate 330and a substrate 372) are shown by only outlines of a dashed line.

The touch panel 100 includes the input device 310 and a display panel370, which are provided to overlap with each other.

The above can be referred to for the structure of the input device 310.FIGS. 25(A) and (B) illustrate the case where the input device 310includes the substrate 330, the electrodes 331, the electrodes 332, theplurality of wirings 341, the plurality of wirings 342, the FPC 350, andthe IC 351.

As the input device 310, for example, a capacitive touch sensor can beused. As the capacitive type, a surface capacitive type, a projectedcapacitive type, and the like are given. In addition, as the projectedcapacitive type, a self capacitive type, a mutual capacitive type, andthe like which differ mainly in the driving method are given. The use ofa mutual capacitive type is preferable because multiple points can bedetected simultaneously. An example of using a projected capacitivetouch sensor will be described below.

Note that without being limited thereto, any of a variety of sensorscapable of sensing the proximity or touch of an object to be sensed,such as a finger or a stylus, can be used as the input device 310.

The display panel 370 includes the substrate 371 and a substrate 372which are provided so as to face each other. In addition, a displayportion 381, a driver circuit 382, a wiring 383, and the like areprovided over the substrate 371. The substrate 371 is also provided withan FPC 373 which is electrically connected to the wiring 383. Inaddition, in the example illustrated in FIGS. 25(A) and (B), an IC 374is provided over the FPC 373.

The display portion 381 includes at least a plurality of pixels. Thepixel includes at least one display element. In addition, it ispreferable that the pixel include a transistor and a display element. Asthe display element, typically, a light-emitting element such as anorganic EL element, a liquid crystal element, or the like can be used.

As the driver circuit 382, for example, a circuit functioning as a scanline driver circuit, a signal line driver circuit, or the like can beused.

The wiring 383 has a function of supplying a signal or electric power tothe display portion 381 or the driver circuit 382. The signal or theelectric power is input from the outside through the FPC 373 or from theIC 374 to the wiring 383.

In addition, in the example illustrated in FIGS. 25(A) and (B), the IC374 is mounted on the FPC 373 by a COF (Chip On Film) method. As the IC374, for example, an IC functioning as a scan line driver circuit, asignal line driver circuit, or the like can be used. Note that it ispossible that the IC 374 is not provided when the display panel 370includes circuits serving as a scan line driver circuit and a signalline driver circuit or when circuits serving as a scan line drivercircuit and a signal line driver circuit are externally provided and asignal for driving the display panel 370 is input through the FPC 373.The IC 374 may also be directly mounted on the substrate 371 by a COG(Chip On Glass) method or the like.

Cross-Sectional Structure Example 1

Next, an example of a cross-sectional structure of the touch panel 100will be described with reference to the drawing. FIG. 26 is a schematiccross-sectional view of the touch panel 100. FIG. 26 illustrates crosssections of a region including the FPC 373, a region including thedriver circuit 382, a region including the display portion 381, and aregion including the FPC 350 in FIG. 25(A).

The substrate 371 and the substrate 372 are attached to each other withan adhesive layer 151. In addition, the substrate 372 and the substrate330 are attached to each other with an adhesive layer 152. Here, astructure including the substrate 371, the substrate 372, and componentsprovided therebetween corresponds to the display panel 370. In addition,a structure including the substrate 330 and components formed over thesubstrate 330 corresponds to the input device 310.

<Display Panel 370>

The display panel 370 is provided with a transistor 201, a transistor202, a transistor 203, a display element 204, a capacitor 205, aconnection portion 206, a wiring 207, and the like.

An insulating layer 211, an insulating layer 212, an insulating layer213, an insulating layer 214, an insulating layer 215, a spacer 216, andthe like are provided over the substrate 371. A portion of theinsulating layer 211 functions as a gate insulating layer of eachtransistor, and another portion thereof functions as a dielectric of thecapacitor 205. The insulating layer 212, the insulating layer 213, andthe insulating layer 214 are provided to cover each transistor, thecapacitor 205, and the like. The insulating layer 214 functions as aplanarization layer. Note that the case where the three insulatinglayers, the insulating layer 212, the insulating layer 213, and theinsulating layer 214, are provided to cover the transistors and the likeis described here; however, without being limited thereto, four or morelayers, a single layer, or two layers may be provided. In addition, theinsulating layer 214 functioning as a planarization layer is notnecessarily provided when not needed.

The display element 204 is provided over the insulating layer 214. Anexample of the case where a top-emission type (top-emission type)organic EL element is used as the display element 204 is described here.The display element 204 includes an EL layer 222 between a firstelectrode 221 and a second electrode 223. The display element 204 emitslight to the second electrode 223 side. The transistor 202, thetransistor 203, the capacitor 205, a wiring, and the like are providedto overlap with a light-emitting region of the display element 204.Thus, the aperture ratio of the display portion 381 can be increased.

In addition, an optical adjustment layer 224 is provided between thefirst electrode 221 and the EL layer 222. The insulating layer 215 isprovided to cover end portions of the first electrode 221 and theoptical adjustment layer 224.

FIG. 26 illustrates a cross section of one pixel as an example of thedisplay portion 381. The case where the pixel includes the transistor202 for current control, the transistor 203 for switching control, andthe capacitor 205 is described here. One of a source and a drain of thetransistor 202 and one electrode of the capacitor 205 are electricallyconnected to the first electrode 221 through an opening provided in theinsulating layer 212, the insulating layer 213, and the insulating layer214.

FIG. 26 also illustrates an example of the driver circuit 382 in whichthe transistor 201 is provided.

In the example illustrated in FIG. 26, the transistor 201 and thetransistor 202 each have a structure in which a semiconductor layerwhere a channel is formed is provided between two gate electrodes. Suchtransistors can have a higher field-effect mobility and thus have higheron-state current than other transistors. Consequently, a circuit capableof high-speed operation can be obtained. Furthermore, the area occupiedby a circuit can be reduced. The use of the transistor having highon-state current can reduce signal delay in wirings and can reducedisplay luminance variation even in a display panel in which the numberof wirings is increased because of increase in size or resolution.

Note that the transistors provided in the driver circuit 382 and thedisplay portion 381 may be transistors having the same structure, ortransistors having different structures may be used in combination.

A material through which impurities such as water or hydrogen do noteasily diffuse is preferably used for at least one of the insulatinglayer 212 and the insulating layer 213 which cover the transistors. Thatis, the insulating layer 212 or the insulating layer 213 can function asa barrier film. Such a structure can effectively suppress diffusion ofthe impurities into the transistors from the outside, and a highlyreliable touch panel can be achieved.

The spacer 216 is provided over the insulating layer 215 and has afunction of adjusting the distance between the substrate 371 and thesubstrate 372. FIG. 26 illustrates the case where there is a gap betweenthe spacer 216 and a light-blocking layer 232, which may however be incontact with each other. In addition, although the spacer 216 isprovided on the substrate 371 side in the structure described here, thespacer 216 may be provided on the substrate 372 side (e.g., closer tothe substrate 371 than the light-blocking layer 232). Alternatively, aparticulate spacer may be used instead of the spacer 216. Although amaterial such as silica can be used for the particulate spacer, anelastic material such as an organic resin or rubber is preferably used.At this time, in some cases, the particulate spacer may be verticallycrushed.

A coloring layer 231, the light-blocking layer 232, and the like areprovided on the substrate 371 side of the substrate 372. Thelight-blocking layer 232 has an opening, and the opening is provided tooverlap with the display region of the display element 204.

As a material that can be used for the light-blocking layer 232, carbonblack, a metal oxide, a composite oxide containing a solid solution of aplurality of metal oxides, or the like can be given. Stacked filmscontaining the material of the coloring layer 231 can also be used forthe light-blocking layer 232. For example, a material containing anacrylic resin can be used for the coloring layer 231, and astacked-layer structure of a film containing a material of a coloringlayer which transmits light of a certain color and a film containing amaterial of a coloring layer which transmits light of another color canbe employed. It is preferable that the coloring layer 231 and thelight-blocking layer 232 be formed using the same material because thesame manufacturing apparatus can be used and the process can besimplified.

For example, as a material that can be used for the coloring layer 231,a metal material, a resin material, a resin material containing apigment or dye, or the like can be given.

In addition, an insulating layer which functions as an overcoat may beprovided to cover the coloring layer 231 and the light-blocking layer232.

The connection portion 206 is provided in a region near an end portionof the substrate 371. The connection portion 206 is electricallyconnected to the FPC 373 through a connection layer 209. In the exampleof the structure illustrated in FIG. 26, the connection portion 206 isformed by stacking a portion of the wiring 207 which is electricallyconnected to the driver circuit 382 and a conductive layer which isformed by processing the same conductive film as that for the firstelectrode 221. When the connection portion 206 is formed by stacking twoor more conductive layers as described above, electric resistance can bereduced and mechanical strength of the connection portion 206 can beincreased.

Furthermore, FIG. 26 illustrates, as an example, a cross-sectionalstructure of an intersection portion 387 where a wiring formed byprocessing the conductive film as the gate electrode of the transistorand a wiring formed by processing the same conductive film as the sourceelectrode and the drain electrode of the transistor cross each other.

<Input Device 310>

The electrode 331 and the electrode 332 are provided on the substrate372 side of the substrate 330. An example in which the electrode 331includes the electrode 333 and the bridge electrode 334 is describedhere. As illustrated in the intersection portion 387 in FIG. 26, theelectrode 332 and the electrode 333 are formed on the same plane. Inaddition, the bridge electrode 334 is provided over an insulating layer161 which covers the electrode 332 and the electrode 333. The bridgeelectrode 334 electrically connects two electrodes 333, between whichthe electrode 332 is provided, through openings formed in the insulatinglayer 161.

A connection portion 106 is provided in a region near an end portion ofthe substrate 330. The connection portion 106 is electrically connectedto the FPC 350 through a connection layer 109. In the example of thestructure illustrated in FIG. 26, the connection portion 106 is formedby stacking a portion of the wiring 342 and a conductive layer which isformed by processing the same conductive film as the bridge electrode334.

As the connection layer 109 or the connection layer 209, an anisotropicconductive film (ACF: Anisotropic Conductive Film), an anisotropicconductive paste (ACP: Anisotropic Conductive Paste), or the like can beused.

The substrate 330 here can be used also as a substrate with which anobject to be sensed, such as a finger or a stylus, is to be in directcontact. In that case, a protective layer (such as a ceramic coat) ispreferably provided over the substrate 330. The protective layer can beformed using an inorganic insulating material such as silicon oxide,aluminum oxide, yttrium oxide, or yttria-stabilized zirconia (YSZ).Alternatively, tempered glass may be used for the substrate 330.Physical or chemical processing by an ion exchange method, a windtempering method, or the like may be performed on the tempered glass, sothat compressive stress is applied on the surface. In the case where thetouch sensor is provided on one side of the tempered glass and theopposite side of the tempered glass is provided on, for example, theoutermost surface of an electronic device for use as a touch surface,the thickness of the whole device can be decreased.

<About Components>

The above-described components will be described below.

A material having a flat surface can be used for the substrate includedin the touch panel. The substrate through which light from the displayelement is extracted is formed using a material that transmits thelight. For example, a material such as glass, quartz, ceramic, sapphire,or an organic resin can be used.

The weight and thickness of the touch panel can be decreased by using athin substrate. Furthermore, a flexible touch panel can be obtained byusing a substrate that has such a thickness to have flexibility.

As glass, for example, alkali-free glass, barium borosilicate glass,aluminoborosilicate glass, or the like can be used.

As materials having flexibility and a light-transmitting property withrespect to visible light, glass that has such a thickness to haveflexibility, polyester resins such as polyethylene terephthalate (PET)and polyethylene naphthalate (PEN), a polyacrylonitrile resin, apolyimide resin, a polymethyl methacrylate resin, a polycarbonate (PC)resin, a polyethersulfone (PES) resin, a polyamide resin, a cycloolefinresin, a polystyrene resin, a polyamide imide resin, a polyvinylchloride resin, a polytetrafluoroethylene (PTFE) resin, and the like aregiven, for example. In particular, a material whose thermal expansioncoefficient is low is preferred, and for example, a polyamide imideresin, a polyimide resin, PET, or the like can be suitably used. Asubstrate in which a glass fiber is impregnated with an organic resin ora substrate whose thermal expansion coefficient is reduced by mixing anorganic resin with an inorganic filler can also be used. A substrateusing such a material is lightweight, and thus, a touch panel using thissubstrate can also be lightweight.

In addition, since the substrate through which light emission is notextracted does not need to have a light-transmitting property, a metalsubstrate or the like can be used in addition to the above-mentionedsubstrates. A metal material or an alloy material, which has highthermal conductivity, is preferable because it can easily conduct heatto the whole sealing substrate and accordingly can prevent a localtemperature rise in the touch panel. To obtain flexibility orbendability, the thickness of a metal substrate is preferably greaterthan or equal to 10 μm and less than or equal to 200 μm, more preferablygreater than or equal to 20 μm and less than or equal to 50 μm.

Although there is no particular limitation on a material of a metalsubstrate, it is favorable to use, for example, a metal such asaluminum, copper, or nickel, an aluminum alloy, an alloy such asstainless steel, or the like.

In addition, it is preferable to use a substrate subjected to insulationtreatment, e.g., a metal substrate whose surface is oxidized or providedwith an insulating film. The insulating film may be formed by, forexample, a coating method such as a spin-coating method or a dippingmethod, an electrodeposition method, an evaporation method, a sputteringmethod, or the like. An oxide film may be formed on the substratesurface by exposure to or heating in an oxygen atmosphere or by ananodic oxidation method or the like.

The flexible substrate may have a stacked structure of a layer of any ofthe above-mentioned materials and a hard coat layer (e.g., a siliconnitride layer) which protects a surface of the touch panel from damageor the like, a layer (e.g., an aramid resin layer) which can dispersepressure, or the like. Furthermore, to suppress a decrease in thelifetime of the light-emitting element due to moisture or the like, aninsulating film with low water permeability, such as a film containingnitrogen and silicon such as a silicon nitride film or a siliconoxynitride film, or a film containing nitrogen and aluminum such as analuminum nitride film, may be provided.

The substrate may be formed by stacking a plurality of layers. Inparticular, when a structure including a glass layer is used, a barrierproperty against water and oxygen can be improved and thus a highlyreliable touch panel can be provided.

For example, a substrate in which a glass layer, an adhesive layer, andan organic resin layer are stacked in this order from the side closer toa light-emitting element can be used. The thickness of the glass layeris greater than or equal to 20 μm and less than or equal to 200 μm,preferably greater than or equal to 25 μm and less than or equal to 100μm. With such a thickness, the glass layer can have both a high barrierproperty against water and oxygen and a high flexibility. In addition,the thickness of the organic resin layer is greater than or equal to 10μm and less than or equal to 200 μm, preferably greater than or equal to20 μm and less than or equal to 50 μm. Providing such an organic resinlayer, occurrence of a crack or a break in the glass layer can besuppressed and mechanical strength can be improved. With such asubstrate that includes such a composite material of a glass materialand an organic resin, a highly reliable and flexible touch panel can beprovided.

The transistors each include a conductive layer functioning as the gateelectrode, the semiconductor layer, a conductive layer functioning asthe source electrode, a conductive layer functioning as the drainelectrode, and an insulating layer functioning as a gate insulatinglayer. FIG. 26 shows the case where a bottom-gate transistor is used.

Note that there is no particular limitation on the structure of thetransistor included in the touch panel of one embodiment of the presentinvention. For example, a staggered transistor or an inverted staggeredtransistor may be used. A top-gate type or a bottom-gate type may alsobe used as the transistor structure. There is no particular limitationon a semiconductor material used for the transistor, and an oxidesemiconductor, silicon, germanium, or the like can be used, for example.

There is no particular limitation on the crystallinity of asemiconductor material used for the transistor, and an amorphoussemiconductor or a semiconductor having crystallinity (amicrocrystalline semiconductor, a polycrystalline semiconductor, asingle crystal semiconductor, or a semiconductor partly includingcrystal regions) may be used. A semiconductor having crystallinity ispreferably used, in which case deterioration of the transistorcharacteristics can be suppressed.

In addition, as a semiconductor material for the semiconductor layer ofthe transistor, an element of Group 14, a compound semiconductor, or anoxide semiconductor can be used, for example. A semiconductor containingsilicon, a semiconductor containing gallium arsenide, an oxidesemiconductor containing indium, or the like can be typically used.

In particular, an oxide semiconductor is preferably used as asemiconductor in which a channel of the transistor is formed. Inparticular, an oxide semiconductor having a wider band gap than siliconis preferably used. A semiconductor material having a wider band gap anda lower carrier density than silicon is preferably used because theoff-state current of the transistor can be reduced.

For example, the oxide semiconductor preferably contains at least indium(In) or zinc (Zn). More preferably, an oxide represented byIn-M-Zn-based oxide (M is a metal such as Al, Ti, Ga, Ge, Y, Zr, Sn, La,Ce, or Hf) is included.

As the semiconductor layer, it is particularly preferable to use anoxide semiconductor film including a plurality of crystal parts. Thec-axes of the crystal parts are oriented substantially perpendicular toa surface on which the semiconductor layer is formed or the top surfaceof the semiconductor layer, and no grain boundary is observed betweenadjacent crystal parts.

Such an oxide semiconductor without grain boundary prevents a crack inan oxide semiconductor film from being caused by stress generated whenthe display panel is curved. Consequently, such an oxide semiconductoris preferably used for a flexible touch panel that is curved when used.

Moreover, the use of such an oxide semiconductor with crystallinity forthe semiconductor layer makes it possible to provide a highly reliabletransistor in which a change in the electric characteristics issuppressed.

In addition, a transistor with an oxide semiconductor whose band gap iswider than that of silicon can hold electric charge stored in acapacitor that is series-connected to the transistor for a long time,owing to its low off-state current. The use of such a transistor inpixels allows a driver circuit to stop while the gray level of an imagedisplayed in display regions is maintained. As a result, a displaydevice with extremely low power consumption can be obtained.

Alternatively, silicon is preferably used as a semiconductor in which achannel of the transistor is formed. Silicon may be amorphous siliconbut is preferably silicon having crystallinity. For example,microcrystalline silicon, polycrystalline silicon, single crystalsilicon, or the like is preferably used. In particular, polycrystallinesilicon can be formed at a lower temperature than single crystal siliconand has higher field-effect mobility and higher reliability thanamorphous silicon. The use of such a polycrystalline semiconductor inpixels increases the aperture ratio of the pixels. Even in the casewhere pixels are provided at extremely high resolution, a scan linedriver circuit and a signal line driver circuit can be formed over thesame substrate as the pixels, and the number of components of anelectronic device can be reduced.

As materials for a conductive layer such as a gate, a source, and adrain of a transistor, and a wiring or an electrode included in thetouch panel, a metal such as aluminum, titanium, chromium, nickel,copper, yttrium, zirconium, molybdenum, silver, tantalum, or tungsten,an alloy containing any of these metals as its main component, or thelike can be given. A single-layer or stacked-layer structure including afilm containing any of these materials can also be used. For example, asingle-layer structure of an aluminum film containing silicon; atwo-layer structure in which an aluminum film is stacked over a titaniumfilm; a two-layer structure in which an aluminum film is stacked over atungsten film; a two-layer structure in which a copper film is stackedover a copper-magnesium-aluminum alloy film; a two-layer structure inwhich a copper film is stacked over a titanium film; a two-layerstructure in which a copper film is stacked over a tungsten film; athree-layer structure in which a titanium film or a titanium nitridefilm, an aluminum film or a copper film over the titanium film or thetitanium nitride film, and a titanium film or a titanium nitride filmthereover are stacked; a three-layer structure in which a molybdenumfilm or a molybdenum nitride film, an aluminum film or a copper filmover the molybdenum film or the molybdenum nitride film, and amolybdenum film or a molybdenum nitride film thereover are stacked; andthe like are given. Note that a transparent conductive materialcontaining indium oxide, tin oxide, or zinc oxide may also be used. Inaddition, copper containing manganese is preferably used becausecontrollability of shape by etching is increased.

In addition, as a light-transmitting material that can be used forconductive layers such as a variety of wirings and electrodes in thetouch panel, a conductive oxide such as indium oxide, indium tin oxide,indium zinc oxide, zinc oxide, or zinc oxide to which gallium is added,or graphene can be used. It is also possible to use a metal materialsuch as gold, silver, platinum, magnesium, nickel, tungsten, chromium,molybdenum, iron, cobalt, copper, palladium, or titanium; or an alloymaterial containing any of these metal materials. Alternatively, anitride of the metal material (e.g., titanium nitride) or the like maybe used. Note that in the case of using the metal material or the alloymaterial (or the nitride thereof), the film thickness is set smallenough to transmit light. Alternatively, a stacked film of any of theabove materials can be used for the conductive layers. For example, astacked film of an alloy of silver and magnesium and indium tin oxide orthe like is preferably used because the conductivity can be increased.

As an insulating material that can be used for the insulating layers,the overcoat, the spacer, and the like, a resin such as an acrylic or anepoxy, a resin having a siloxane bond, and an inorganic insulatingmaterial such as silicon oxide, silicon oxynitride, silicon nitrideoxide, silicon nitride, or aluminum oxide can be used.

In addition, the light-emitting element is preferably provided between apair of insulating films with low water permeability, in which caseimpurities such as water can be prevented from entering thelight-emitting element. Thus, a decrease in device reliability can beprevented.

As the insulating film with low water permeability, a film containingnitrogen and silicon such as a silicon nitride film or a silicon nitrideoxide film, a film containing nitrogen and aluminum such as an aluminumnitride film, and the like are given. Alternatively, a silicon oxidefilm, a silicon oxynitride film, an aluminum oxide film, or the like maybe used.

For example, the water vapor transmittance of the insulating film withlow water permeability is lower than or equal to 1×10⁻⁵ [g/(m²·day)],preferably lower than or equal to 1×10⁻⁶ [g/(m²·day)], more preferablylower than or equal to 1×10⁻⁷ [g/(m²·day)], more preferably lower thanor equal to 1×10⁻⁸ [g/(m²·day)].

For the adhesive layers, any of a variety of types of curable adhesives,e.g., a light curable adhesive such as a UV curable adhesive, a reactivecurable adhesive, a heat curable adhesive, and an anaerobic adhesive,can be used. As these adhesives, an epoxy resin, an acrylic resin, asilicone resin, a phenol resin, a polyimide resin, an imide resin, a PVC(polyvinyl chloride) resin, a PVB (polyvinyl butyral) resin, an EVA(ethylene vinyl acetate) resin, and the like are given. In particular, amaterial with low moisture permeability, such as an epoxy resin, ispreferred. Alternatively, a two-component type resin may be used.Alternatively, an adhesive sheet or the like may be used.

Furthermore, the resin may include a drying agent. For example, asubstance that adsorbs moisture by chemical adsorption, such as an oxideof an alkaline earth metal (e.g., calcium oxide or barium oxide), can beused. Alternatively, a substance that adsorbs moisture by physicaladsorption, such as zeolite or silica gel, may be used. The drying agentis preferably included because it can prevent an impurity such asmoisture from entering a functional element, thereby improving thereliability of the display panel.

In addition, a filler with a high refractive index or a light-scatteringmember may be mixed into the resin, in which case the efficiency oflight extraction from the light-emitting element can be improved. Forexample, titanium oxide, barium oxide, zeolite, zirconium, or the likecan be used.

As the light-emitting element, a self-luminous element can be used, andan element whose luminance is controlled by current or voltage isincluded in the category of the light-emitting element. For example, alight-emitting diode (LED), an organic EL element, an inorganic ELelement, or the like can be used.

The light-emitting element may be a top-emission type, a bottom-emissiontype, or a dual-emission type. A conductive film that transmits visiblelight is used as the electrode through which light is extracted. Inaddition, a conductive film that reflects visible light is preferablyused as the electrode through which light is not extracted.

The EL layer includes at least a light-emitting layer. In addition tothe light-emitting layer, the EL layer may further include a layercontaining any of a substance with a high hole-injection property, asubstance with a high hole-transport property, a hole-blocking material,a substance with a high electron-transport property, a substance with ahigh electron-injection property, a substance with a bipolar property (asubstance with a high electron-transport property and a highhole-transport property), and the like.

For the EL layer, either a low-molecular compound or a high-molecularcompound can be used, and an inorganic compound may also be included.Each of the layers included in the EL layer can be formed by a methodsuch as an evaporation method (including a vacuum evaporation method), atransfer method, a printing method, an inkjet method, or a coatingmethod.

When a voltage higher than the threshold voltage of the light-emittingelement is applied between a cathode and an anode, holes are injected tothe EL layer from the anode side and electrons are injected from thecathode side. The injected electrons and holes are recombined in the ELlayer and a light-emitting substance contained in the EL layer emitslight.

In the case where a light-emitting element emitting white light is usedas the light-emitting element, the EL layer preferably contains two ormore kinds of light-emitting substances. For example, the light-emittingsubstances are selected such that the colors of light emission of two ormore light-emitting substances are complementary to each other, so thatwhite light emission can be obtained. For example, it is preferable tocontain two or more selected from light-emitting substances emittinglight of R (red), G (green), B (blue), Y (yellow), 0 (orange), and thelike and light-emitting substances emitting light containing two or morecolors of spectral components of R, G, and B. In addition, alight-emitting element whose emission spectrum has two or more peaks inthe wavelength range of a visible light region (e.g., 350 nm-750 nm) ispreferably used. In addition, an emission spectrum of a material havinga peak in a yellow wavelength range preferably includes spectralcomponents also in green and red wavelength ranges.

More preferably, a light-emitting layer containing a light-emittingmaterial emitting light of one color and a light-emitting layercontaining a light-emitting material emitting light of another color arestacked in the EL layer. For example, the plurality of light-emittinglayers in the EL layer may be stacked in contact with each other or maybe stacked with a region which does not include any light-emittingmaterial therebetween. For example, between a fluorescent layer and aphosphorescent layer, a region containing the same material as one inthe fluorescent layer or phosphorescent layer (for example, a hostmaterial or an assist material) and no light-emitting material may beprovided. This facilitates the manufacture of the light-emitting elementand reduces the drive voltage.

In addition, the light-emitting element may be a single elementincluding one EL layer or a tandem element in which a plurality of ELlayers are stacked with a charge generation layer therebetween.

The conductive film that transmits visible light can be formed using,for example, indium oxide, indium tin oxide, indium zinc oxide, zincoxide, zinc oxide to which gallium is added, or the like. Alternatively,a metal material such as gold, silver, platinum, magnesium, nickel,tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, ortitanium; an alloy containing any of these metal materials; a nitride ofany of these metal materials (e.g., titanium nitride); or the like canbe formed thin so as to have a light-transmitting property to be used.Alternatively, a stacked film of any of the above materials can be usedfor the conductive layers. For example, a stacked film of an alloy ofsilver and magnesium and indium tin oxide or the like is preferablyused, in which case conductivity can be increased. Alternatively,graphene or the like may be used.

For the conductive film that reflects visible light, for example, ametal material such as aluminum, gold, platinum, silver, nickel,tungsten, chromium, molybdenum, iron, cobalt, copper, or palladium or analloy containing any of these metal materials can be used. Furthermore,lanthanum, neodymium, germanium, or the like may be added to the metalmaterial or the alloy. Alternatively, an alloy containing aluminum andtitanium, nickel, or neodymium (an aluminum alloy) may be used.Alternatively, an alloy containing silver and copper, palladium, ormagnesium may be used. An alloy containing silver and copper ispreferable because of its high heat resistance. Furthermore, when ametal film or a metal oxide film is stacked in contact with an aluminumfilm or an aluminum alloy film, oxidation of the aluminum alloy film canbe suppressed. As a material for the metal film or the metal oxide film,titanium, titanium oxide, and the like are given. Alternatively, theabove conductive film that transmits visible light and a film containinga metal material may be stacked. For example, a stacked film of silverand indium tin oxide, a stacked film of an alloy of silver and magnesiumand indium tin oxide, or the like can be used.

Each of the electrodes can be formed by an evaporation method or asputtering method. Alternatively, a discharging method such as an inkjetmethod, a printing method such as a screen printing method, or a platingmethod may be used.

The above is the description of the components.

Examples whose structures are partly different from that of the abovecross-sectional Structure Example 1 will be described below withreference to the drawings. Note that the description of the portionsalready described is omitted and different portions are described below.

Cross-Sectional Structure Example 2

FIG. 27 illustrates a cross-sectional structure example of the touchpanel 100 whose structure is partly different from that in FIG. 26. Notethat the description of the portions already described is omitted anddifferent portions are described.

In FIG. 27, in the transistor 201 and the transistor 202, conductivelayers functioning as their second gates are provided between theinsulating layer 213 and the insulating layer 214. Such a structure ispreferable because the voltage to be applied to the second gates can belowered as compared with the structure in FIG. 26.

In addition, FIG. 27 illustrates an example of the case where thedisplay element 204 is formed by a separate coloring method.Specifically, in pixels for different colors, EL layers 222 which emitlight of different colors are formed. In addition, in a region outsidethe light-emitting region of the display element 204, an end portion ofthe EL layer 222 is covered with the second electrode 223. The EL layer222 can be formed by, for example, an evaporation method using a metalmask, a printing method, an inkjet method, or the like.

In addition, in the example illustrated in FIG. 27, the opticaladjustment layer 224 and the coloring layer 231 illustrated in FIG. 26are not provided.

Note that the structure of the transistors, the structure of the displayelement 204, and the like which are illustrated here can be interchangedwith any of the structures of the transistors, display elements, and thelike which are illustrated in FIG. 26 and in the followingcross-sectional structures.

The above is the description of the cross-sectional Structure Example 2.

Cross-Sectional Structure Example 3

A touch panel illustrated in FIG. 28 includes a substrate 111 and asubstrate 112. The substrate 111 and the substrate 372 are bonded toeach other with the adhesive layer 152, and the substrate 111 and thesubstrate 112 are bonded to each other with an adhesive layer 153.

The electrode 332, the wiring 342, and the like are formed over thesubstrate 111. In addition, the electrode 331, the wiring 341 (notillustrated), and the like are formed over the substrate 112. In FIG.28, the FPC 350 is provided over the substrate 111; an FPC is similarlyconnected to the substrate 112 in a region not illustrated in thedrawing.

In the case where two substrates are used in the structure of the inputdevice 310 as described above, substrates as thin as, or thinner than,the substrate 371 and the substrate 372 are preferably used as thesubstrate 111 and the substrate 112. It is particularly preferable touse a material having flexibility for the substrate 111 and thesubstrate 112, in which case the thickness of the touch panel 100 can bedecreased.

Alternatively, a protective substrate 130 may be provided over thesubstrate 112 with an adhesive layer 154 therebetween as illustrated inFIG. 28. A surface of the protective substrate 130 on a side opposite tothe substrate 112 side functions as a touch surface. The abovedescription of the substrate 330 can be referred to for a material ofthe protective substrate 130.

Cross-Sectional Structure Example 4

A touch panel illustrated in FIG. 29 includes a substrate 113. Thesubstrate 113 and the substrate 372 are bonded to each other with theadhesive layer 152.

The substrate 113 is provided with the electrode 332, the wiring 342,and the like on one side. The substrate 113 is also provided with theelectrode 331, the wiring 341, and the like on the other side. That is,the electrodes and wirings in the touch sensor are provided on bothsides of the substrate 113.

In addition, FIG. 29 illustrates an example in which an FPC 350 a and aconnection layer 109 a are provided in a connection portion 106 a wherepart of the wiring 342 is exposed, and an FPC 350 b and a connectionlayer 109 b are provided in a connection portion 106 b where part of thewiring 341 is exposed. Note that the connection portion 106 a and theconnection portion 106 b may overlap with each other in a plan view, ormay be displaced positioned so as not to overlap with each other.

Cross-Sectional Structure Example 5

In a touch panel illustrated in FIG. 30, the electrodes and the like inthe touch sensor are provided on the side of the substrate 372 oppositeto the substrate 371. Specifically, the bridge electrode 334 and theinsulating layer 161 covering part of the bridge electrode 334 areprovided over the substrate 372, and the electrode 331, the electrode332, the wiring 341 (not illustrated), the wiring 342, and the like areprovided over the insulating layer 161.

In addition, as illustrated in FIG. 30, the protective substrate 130 andthe substrate 372 may be bonded to each other with the adhesive layer152.

In such a structure, the input device 310 and the display panel 370 canshare the substrate; thus, the thickness of the touch panel can besignificantly decreased.

Cross-Sectional Structure Example 6

FIG. 31 illustrates an example of the case where the structure of thetouch sensor illustrated in FIG. 30 is combined with the structure ofthe touch panel illustrated in FIG. 27 where the light-emitting elementformed by a separate coloring method is used as the display element 204.In addition, in the example illustrated in FIG. 31, the coloring layer231 and the light-blocking layer 232 are not provided.

Cross-Sectional Structure Example 7

In a touch panel illustrated in FIG. 32, the electrodes and the like inthe touch sensor are provided on the substrate 371 side of the substrate372. Specifically, the electrode 332, the electrode 333, the wiring 341(not illustrated), the wiring 342, and the like, and the insulatinglayer 161 covering these components are provided over the substrate 372;and the bridge electrode 334 and the like are provided over theinsulating layer 161.

In addition, an insulating layer 233 is provided to cover the electrodesand the like in the touch sensor. Furthermore, the coloring layer 231,the light-blocking layer 232, and the like are provided over theinsulating layer 233.

In such a structure, the input device 310 and the display panel 370 canshare the substrate, and one surface of the substrate 372 can be used asa touch surface; thus, the thickness of the touch panel 100 can befurther decreased.

Cross-Sectional Structure Example 8

FIG. 33 illustrates a modification example of the touch panelillustrated in FIG. 32.

The touch panel in FIG. 33 has a stacked-layer structure including asubstrate 391, an adhesive layer 392, a substrate 393, and an insulatinglayer 394 in place of the substrate 371. The touch panel also has astacked-layer structure including a substrate 191, an adhesive layer192, a substrate 193, and an insulating layer 194 in place of thesubstrate 372.

A material through which impurities such as water or hydrogen do noteasily diffuse can be used for the insulating layer 394 and theinsulating layer 194. Such a structure can effectively suppressdiffusion of the impurities from the outside into the display element204 and the transistors even in the case of using a material permeableto moisture for the substrate 391, the substrate 393, the substrate 191,and the substrate 193, and a highly reliable touch panel can beachieved.

A material such as a resin having flexibility can be used for thesubstrate 393 and the substrate 193. Films having flexibility or thelike are preferably used as the substrate 391 and the substrate 191.With the use of a material having flexibility for these substrates, abendable touch panel can be achieved.

Cross-Sectional Structure Example 9

In a touch panel illustrated in FIG. 34, the light-blocking layer 232 isprovided between the electrodes and the like in the touch sensor and thesubstrate 372. Specifically, the light-blocking layer 232 is providedover the substrate 372, and an insulating layer 234 is provided to coverthe light-blocking layer 232. The electrode 332, the electrode 333, thewiring 341 (not illustrated), the wiring 342, and the insulating layer161 covering these components are provided over the insulating layer234; and the bridge electrode 334 and the like are provided over theinsulating layer 161. In addition, the insulating layer 233 is providedover the bridge electrode 334 and the insulating layer 161, and thecoloring layer 231 is provided over the insulating layer 233.

The insulating layer 233 and the insulating layer 234 have a function asa planarization film. Note that the insulating layer 233 and theinsulating layer 234 are not necessarily provided when not needed.

In such a structure, the light-blocking layer 232 provided closer to theviewing side than the electrodes and the like in the touch sensor canprevent the electrode and the like from being visible. Thus, a touchpanel with not only a small thickness but also improved visibility canbe achieved.

Cross-Sectional Structure Example 10

FIG. 35 illustrates a modification example of the touch panelillustrated in FIG. 34.

The touch panel in FIG. 35 has a stacked-layer structure including asubstrate 391, an adhesive layer 392, and an insulating layer 394 inplace of the substrate 371. The touch panel also has a stacked-layerstructure including a substrate 191, an adhesive layer 192, and aninsulating layer 194 in place of the substrate 372.

With the use of a material having flexibility for the substrate 391 andthe substrate 191, a bendable touch panel can be achieved.

Cross-Sectional Structure Example 11

FIG. 36 illustrates a cross-sectional structure example of a touch panelin the case where a liquid crystal display device is used as the displaypanel 370. In the touch panel illustrated in FIG. 36, a liquid crystalelement is used as a display element 208. In addition, the touch panelincludes a polarizing plate 131, a polarizing plate 132, and a backlight133.

In the example illustrated here, a liquid crystal element using an FFS(Fringe Field Switching) mode is used as the display element 208. Thedisplay element 208 includes an electrode 252, an electrode 251, andliquid crystal 253. The electrode 251 is provided over the electrode 252with an insulating layer 254 provided therebetween, and has a comb-likeshape or a shape provided with a slit.

In addition, an overcoat 255 is provided to cover the coloring layer 231and the light-blocking layer 232. The overcoat 255 has a function ofpreventing a pigment or the like which is included in the coloring layer231 or the light-blocking layer 232 from diffusing into the liquidcrystal 253.

In addition, surfaces of the overcoat 255, the insulating layer 254, theelectrode 251, and the like which are in contact with the liquid crystal253 may be provided with alignment films for controlling the orientationof the liquid crystal 253.

In FIG. 36, the polarizing plate 131 is bonded to the substrate 371 withan adhesive layer 157. In addition, the backlight 133 is bonded to thepolarizing plate 131 with an adhesive layer 158. In addition, thepolarizing plate 132 is positioned between the substrate 372 and thesubstrate 330. The polarizing plate 132 is bonded to the substrate 372with an adhesive layer 155, and is bonded to the substrate 330(specifically, a portion of the insulating layer 161 formed over thesubstrate 330) with an adhesive layer 156.

Although the liquid crystal element using an FFS mode is describedabove, a VA (Vertical Alignment) mode, a TN (Twisted Nematic) mode, anIPS (In-Plane-Switching) mode, an ASM (Axially Symmetric alignedMicro-cell) mode, an OCB (Optically Compensated Birefringence) mode, anFLC (Ferroelectric Liquid Crystal) mode, an AFLC (AntiFerroelectricLiquid Crystal) mode, or the like can be used.

In addition, as the liquid crystal, thermotropic liquid crystal,low-molecular liquid crystal, high-molecular liquid crystal,ferroelectric liquid crystal, anti-ferroelectric liquid crystal, polymerdispersed liquid crystal (PDLC: Polymer Dispersed Liquid Crystal), orthe like can be used. Moreover, liquid crystal exhibiting a blue phaseis preferably used because an alignment film is not needed and a wideviewing angle is obtained.

Cross-Sectional Structure Example 12

FIG. 37 illustrates a cross-sectional structural example of a touchpanel in the case where a liquid crystal display device is used as thedisplay panel 370. In the touch panel illustrated in FIG. 37, thepolarizing plate 132 is provided closer to the viewing side than theelectrodes and the like in the touch sensor. Specifically, a substrate114 provided with the electrode 331, the electrode 332, and the like isbonded to the substrate 372 with the adhesive layer 152, and thepolarizing plate 132 is bonded to the substrate 114 with the adhesivelayer 155. In addition, the protective substrate 130 bonded to thepolarizing plate 132 with the adhesive layer 156 is provided closer tothe viewing side than the polarizing plate 132.

A film having flexibility or the like is preferably used as thesubstrate 114 because the thickness of the touch panel can be decreased.

Cross-Sectional Structure Example 13

FIG. 38 illustrates a cross-sectional structure example of a touch panelin the case where a liquid crystal display device is used as the displaypanel. In the example of the touch panel illustrated in FIG. 38, theelectrodes and the like of the touch sensor are formed on the substrate371 side of the substrate 372. Specifically, the electrode 332, theelectrode 333, the wiring 341 (not illustrated), the wiring 342, and thelike, and the insulating layer 161 covering these components areprovided over the substrate 372; and the bridge electrode 334 and thelike are provided over the insulating layer 161. In addition, theinsulating layer 233 is provided to cover the electrodes and the like inthe touch sensor. In addition, the coloring layer 231, thelight-blocking layer 232, and the like are provided over the insulatinglayer 233.

In addition, the polarizing plate 132 is bonded to the opposite side ofthe substrate 372 with the adhesive layer 155. In addition, theprotective substrate 130 is bonded to the polarizing plate 132 with theadhesive layer 156.

In such a structure, the input device and the display panel can sharethe substrate and one surface of the substrate 372 can be used as atouch surface; thus, the thickness of the touch panel can be furtherdecreased.

Cross-Sectional Structure Example 14

FIG. 39 illustrates a cross-sectional structure example of a touch panelin the case where a liquid crystal display device is used as the displaypanel. In the example of the touch panel illustrated in FIG. 39, theelectrodes and the like in the touch sensor are provided on a side ofthe substrate 372 opposite to the substrate 371 side. Specifically, thebridge electrode 334 and the insulating layer 161 covering part of thebridge electrode 334 are provided over a surface of the substrate 372 ona side opposite to the side where the coloring layer 231 and the likeare provided; and the electrode 331, the electrode 332, the wiring 341(not illustrated), the wiring 342, and the like are provided over theinsulating layer 161. In addition, the polarizing plate 132 is attachedto the substrate 372 with the adhesive layer 152, and the protectivesubstrate 130 is attached to the polarizing plate 132 with the adhesivelayer 156.

Cross-Sectional Structure Example 15

FIG. 40 illustrates an example of the case where a top-gate transistoris used as each of the transistor 201, the transistor 202, and thetransistor 203 in the cross-sectional structural example illustrated inFIG. 26.

Each of the transistors includes a semiconductor layer 261, and a gateelectrode is provided over the semiconductor layer 261 with theinsulating layer 211 provided therebetween. In addition, thesemiconductor layer 261 may include a low-resistance region 262.

Source electrodes and drain electrodes of the transistors are providedover the insulating layer 213 and electrically connected to the regions262 through openings provided in the insulating layer 213, theinsulating layer 212, and the insulating layer 211.

FIG. 40 also illustrates an example in which the capacitor 205 has astacked-layer structure including a layer formed by processing the samesemiconductor film as the semiconductor layer 261, the insulating layer211, and a layer formed by processing the same conductive film as thegate electrode. It is preferable here that a region 263 having a higherconductivity than a region in which a channel of the transistor isformed be formed in a portion of the semiconductor film of the capacitor205.

The region 262 and the region 263 can be, for example, a regioncontaining a larger amount of impurities than the region where thechannel of the transistor is formed, a region with a high carrierconcentration, a region with low crystallinity, or the like. An impuritywhich can increase the conductivity depends on a semiconductor used forthe semiconductor layer 261; typically, an element that can impartn-type conductivity, such as phosphorus, an element that can impartp-type conductivity, such as boron, a rare gas such as helium, neon, orargon, hydrogen, lithium, sodium, magnesium, aluminum, nitrogen,fluorine, potassium, calcium, or the like can be given. In addition tothe above, titanium, iron, nickel, copper, zinc, silver, indium, tin, orthe like also functions as an impurity which influences the conductivityof the semiconductor. For example, the region 262 and the region 263contain the above impurity in a larger amount than the region where thechannel of the transistor is formed.

Cross-Sectional Structure Example 16

FIG. 41 illustrates an example of the case where top-gate transistorsare used as the transistor 201 and the transistor 203 in thecross-sectional structural example illustrated in FIG. 36.

Modification Example

FIGS. 42(A) and (B) are perspective schematic views of the touch panel100 whose structure is partly different from the structure illustratedin each drawing of FIG. 25.

In FIGS. 42(A) and (B), the substrate 372 of the display panel 370 isprovided with the input device 310. In addition, the wiring 341, thewiring 342, and the like of the input device 310 are electricallyconnected to the FPC 373 provided for the display panel 370 through aconnection portion 385.

With such a structure, the FPC connected to the touch panel 100 can beprovided only on one substrate side (on the substrate 371 side here). Inaddition, although two or more FPCs may be attached to the touch panel100, it is preferable that the touch panel 100 be provided with one FPC373 and the FPC 373 has a function of supplying signals to both thedisplay panel 370 and the input device 310 as illustrated in FIGS. 42(A)and (B), for the simplicity of the structure.

In addition, in that case, the IC 374 can have a function of driving theinput device 310. Alternatively, an IC for driving the input device 310may further be provided. Alternatively, an IC for driving the inputdevice 310 may be mounted on the substrate 371.

FIG. 43 illustrates the cross sections of a region including the FPC373, a region including the connection portion 385, a region includingthe driver circuit 382, and a region including the display portion 381in FIG. 42.

In the connection portion 385, one of the wirings 342 (or the wirings341) and one of the wirings 207 are electrically connected to each otherthrough a connector 386.

As the connector 386, a conductive particle can be used, for example. Asthe conductive particle, a particle of an organic resin, silica, or thelike whose surface is coated with a metal material can be used. It ispreferable to use nickel or gold as the metal material because contactresistance can be decreased. It is also preferable to use a particlecoated with layers of two or more kinds of metal materials, such as aparticle coated with nickel and further with gold. In addition, as theconnector 386, a material capable of elastic deformation or plasticdeformation is preferably used. As illustrated in FIG. 43, theconductive particle here has a shape that is vertically crushed in somecases. Accordingly, the contact area between the connector 386 and aconductive layer electrically connected to the connector 386 can beincreased, thereby reducing contact resistance and suppressing thegeneration of problems such as disconnection.

The connector 386 is preferably provided so as to be covered with theadhesive layer 151. For example, a paste or the like for forming theadhesive layer 151 may be applied, and then, the connectors 386 may bescattered in the connection portion 385. By providing the connectionportion 385 in a portion where the adhesive layer 151 is provided, notonly a structure in which the adhesive layer 151 is also provided overthe display element 204 as illustrated in FIG. 43 (also referred to as asolid sealing structure) but also, for example, a structure in which theadhesive layer 151 is provided in the peripheral portion, such as alight-emitting device, a liquid crystal display device, or the likehaving a hollow sealing structure, can be similarly applied.

The above is the description of the cross-sectional structure examples.

Structure Example of in-Cell Touch Panel

Although the case where the electrodes in the touch sensor are formedover a substrate different from a substrate where the display elementand the like are provided is described above, one or both of the pair ofelectrodes in the touch sensor may be formed over the substrate wherethe display element and the like are provided.

A structure example of a touch panel incorporating the touch sensor intoa display portion including a plurality of pixels will be describedbelow. Here, an example in which a liquid crystal element is used as adisplay element provided in the pixel is shown.

FIG. 44(A) is an equivalent circuit diagram of part of a pixel circuitprovided in the display portion of the touch panel exemplified in thisstructure example.

One pixel includes at least a transistor 3503 and a liquid crystalelement 3504. In addition, a gate of the transistor 3503 is electricallyconnected to a wiring 3501 and one of a source and a drain thereof iselectrically connected to a wiring 3502.

The pixel circuit includes a plurality of wirings extending in the Xdirection (e.g., a wiring 3510_1 and a wiring 3510_2) and a plurality ofwirings extending in the Y direction (e.g., a wiring 3511). They areprovided to intersect with each other, and capacitance is formedtherebetween.

In addition, in the pixels provided in the pixel circuit, one electrodesof the liquid crystal elements of some of a plurality of pixels adjacentto each other are electrically connected to each other to form oneblock. The block is classified into two types: an island-shaped block(e.g., a block 3515_1 or a block 3515_2) and a linear block (e.g., ablock 3516) extending in the Y direction. Note that only part of thepixel circuit is illustrated in FIG. 44; actually, these two kinds ofblocks are repeatedly arranged in the X direction and the Y direction.

The wiring 3510_1 (or 3510_2) extending in the X direction iselectrically connected to the island-shaped block 3515_1 (or the block3515_2). Although not illustrated, the wiring 3510_1 extending in the Xdirection is electrically connected to a plurality of island-shapedblocks 3515_1 which are provided discontinuously along the X directionwith the linear blocks therebetween. Furthermore, the wiring 3511extending in the Y direction is electrically connected to the linearblock 3516.

FIG. 44(B) is an equivalent circuit diagram illustrating the connectionstructure between the plurality of wirings 3510 extending in the Xdirection and the plurality of wirings 3511 extending in the Ydirection. Input voltage or a common potential can be input to each ofthe wirings 3510 extending in the X direction. Furthermore, a groundpotential can be input to each of the wirings 3511 extending in the Ydirection, or the wirings 3511 can be electrically connected to adetection circuit.

Operation of the above-described touch panel is described with referenceto FIGS. 45(A) and (B) below.

Here, one frame period is divided into a writing period and a sensingperiod. The writing period is a period during which image data iswritten to a pixel, and the wirings 3510 (also referred to as gatelines) are sequentially selected. On the other hand, the sensing periodis a period during which sensing is performed by a touch sensor, and thewirings 3510 extending in the X direction are sequentially selected andinput voltage is input.

FIG. 45(A) is an equivalent circuit diagram in the writing period. Inthe writing period, a common potential is input to both the wiring 3510extending in the X direction and the wiring 3510 extending in the Ydirection.

FIG. 45(B) is an equivalent circuit diagram at some point in time in thesensing period. In the sensing period, each of the wirings 3511extending in the Y direction is electrically connected to the detectioncircuit. In addition, input voltage is input to the wirings 3510extending in the X direction which are selected, and a common potentialis input to other wirings 3510.

Note that the driving method described here can be applied to not onlyan in-cell type but also the above-described touch panels, and can beused in combination with the method described in the driving methodexample.

It is preferable that a period during which an image is written and aperiod during which sensing is performed by a touch sensor be separatelyprovided as described above. Thus, a decrease in sensitivity of thetouch sensor caused by noise generated when data is written to a pixelcan be suppressed.

<Example of Manufacturing Method>

Here, a method for manufacturing a flexible touch panel will bedescribed.

Here, for convenience, a structure including a pixel and a circuit, astructure including an optical member such as a color filter, astructure including electrodes and wirings in a touch sensor, or thelike is referred to as an element layer. An element layer includes adisplay element, for example, and may include a wiring electricallyconnected to the display element or an element such as a transistor usedin a pixel or a circuit in addition to the display element.

In addition, here, a support (e.g., the substrate 391 or the substrate191 in FIG. 35) with an insulating surface where an element layer isformed is referred to as a substrate.

As a method for forming an element layer over a flexible substrateprovided with an insulating surface, there are a method in which anelement layer is formed directly over a substrate, and a method in whichan element layer is formed over a supporting base that is different froma substrate and then the element layer is separated from the supportingbase and transferred to the substrate.

In the case where a material of the substrate can withstand heat appliedin a process for forming the element layer, it is preferable that theelement layer be formed directly over the substrate, in which case theprocess can be simplified. At this time, the element layer is preferablyformed in a state where the substrate is fixed to the supporting base,in which case transfer thereof in an apparatus and between apparatusescan be easy.

In addition, in the case of employing the method in which the elementlayer is formed over the supporting base and then transferred to thesubstrate, first, a separation layer and an insulating layer are stackedover the supporting base, and then, the element layer is formed over theinsulating layer. Next, the element layer is separated from thesupporting base and then transferred to the substrate. In that case, amaterial is selected that would cause separation at the interfacebetween the supporting base and the separation layer, at the interfacebetween the separation layer and the insulating layer, or in theseparation layer.

For example, it is preferable that a stacked layer of a layer includinga high-melting-point metal material, such as tungsten, and a layerincluding an oxide of the metal material be used as the separationlayer, and a stacked layer of a plurality of silicon nitride and siliconoxynitride be used as the insulating layer over the separation layer.The use of the high-melting-point metal material is preferable becausethe degree of freedom of the process for forming the element layer canbe increased.

The separation may be performed by application of mechanical power, byetching of the separation layer, by dripping of a liquid into part ofthe separation interface to penetrate the entire separation interface,or the like. Alternatively, the separation may be performed by heatingthe separation interface by utilizing a difference in thermal expansion.

In addition, the separation layer is not necessarily provided in thecase where separation can occur at the interface between the supportingbase and the insulating layer. For example, glass is used as thesupporting base and an organic resin such as polyimide is used as theinsulating layer, a separation trigger is formed by locally heating partof the organic resin by laser light or the like, and separation isperformed at the interface between the glass and the insulating layer.Alternatively, a metal layer may be provided between the supporting baseand the insulating layer formed of an organic resin, and separation maybe performed at the interface between the metal layer and the insulatinglayer by heating the metal layer by feeding a current to the metallayer. Alternatively, a layer of a light-absorbing material (e.g., ametal, a semiconductor, or an insulator) may be provided between thesupporting base and the insulating layer formed of an organic resin andmay be locally heated by being irradiated with light such as laser lightto form a separation trigger. In these methods, the insulating layerformed of an organic resin can be used as a substrate.

As a flexible substrate, for example, polyester resins such aspolyethylene terephthalate (PET) and polyethylene naphthalate (PEN), apolyacrylonitrile resin, a polyimide resin, a polymethyl methacrylateresin, a polycarbonate (PC) resin, a polyethersulfone (PES) resin, apolyamide resin, a cycloolefin resin, a polystyrene resin, a polyamideimide resin, a polyvinyl chloride resin, and the like are given. Inparticular, a material whose thermal expansion coefficient is low ispreferred, and for example, a polyamide imide resin, a polyimide resin,PET, or the like with a thermal expansion coefficient of 30×10⁻⁶/K orless can be suitably used. In addition, a substrate in which a fibrousbody is impregnated with a resin (also referred to as prepreg) or asubstrate whose thermal expansion coefficient is reduced by mixing aninorganic filler with an organic resin can also be used.

In the case where a fibrous body is included in the above material, ahigh-strength fiber of an organic compound or an inorganic compound isused as the fibrous body. The high-strength fiber is specifically afiber with a high tensile elastic modulus or a fiber with a high Young'smodulus. As typical examples thereof, a polyvinyl alcohol based fiber, apolyester based fiber, a polyamide based fiber, a polyethylene basedfiber, an aramid based fiber, a polyparaphenylene benzobisoxazole fiber,a glass fiber, and a carbon fiber can be given. As the glass fiber, aglass fiber using E glass, S glass, D glass, Q glass, or the like can begiven. These fibers may be used in a state of a woven fabric or anonwoven fabric, and a structure body in which this fibrous body isimpregnated with a resin and the resin is cured may be used as theflexible substrate. The structure body including the fibrous body andthe resin is preferably used as the flexible substrate, in which casethe reliability against bending or breaking due to local pressure can beincreased.

Alternatively, glass, metal, or the like that is thin enough to haveflexibility can be used as the substrate. Alternatively, a compositematerial in which glass and a resin material are bonded to each othermay be used.

In the structure illustrated in FIG. 35, for example, a first separationlayer and the insulating layer 394 are formed in this order over a firstsupporting base, and then, upper components are formed. Separately, asecond separation layer and the insulating layer 194 are formed in thisorder over a second supporting base, and then, upper components areformed. Next, the first supporting base and the second supporting baseare attached to each other with the adhesive layer 151. After that,separation at the interface between the second separation layer and theinsulating layer 194 is performed so that the second supporting base andthe second separation layer are removed, and then, the substrate 191 isattached to the insulating layer 194 with the adhesive layer 192.Furthermore, separation at the interface between the first separationlayer and the insulating layer 394 is performed so that the firstsupporting base and the first separation layer are removed, and then,the substrate 391 is attached to the insulating layer 394 with theadhesive layer 392. Note that either side may be subjected to separationand attachment first.

The above is the description of the method for manufacturing a flexibletouch panel.

The input/output device (the touch panel), the input device (the touchsensor), the output device (the display panel), and the like which aredescribed as examples in this embodiment can be applied to the displayportions of the electronic device 21 and the display device 11 which aredescribed as examples in Embodiment 1. In addition, the flexible displaypanel or touch panel can be applied to the display portion 24 providedalong the curved surface of the housing 22 or the display portion 13 ofthe display device 11 which is intended to be bent. In addition, theflexible display panel or touch panel, or alternatively, an inflexibledisplay panel or touch panel may be applied to the display portion 23which performs display along a flat surface.

At least part of this embodiment can be implemented in combination withany of the other embodiments described in this specification asappropriate.

REFERENCE NUMERALS

-   10: system-   11: display device-   12: support-   13: display portion-   14: connection portion-   14 a: movable portion-   14 b: detachment portion-   15: connection mechanism-   16: terminal-   17: window portion-   18: fastener-   20: electronic device-   21: electronic device-   22: housing-   23: display portion-   24: display portion-   25: support mechanism-   26: engagement portion-   27: connection mechanism-   28: terminal-   29: projection-   31: hinge-   31 a: portion-   31 b: portion-   32: immovable portion-   36: rotation axis-   37: rotation axis-   38: rotation axis-   50: arithmetic portion-   51: memory device-   52: detection portion-   53: wireless communication portion-   54: antenna-   55: power management portion-   56: power reception portion-   57: battery module-   58: shape detection portion-   60: external interface-   61: camera module-   62: sound controller-   63: audio output portion-   64: audio input portion-   65: sensor-   71: touch panel-   72: display controller-   73: touch sensor controller-   81: touch panel-   82: display controller-   83: touch sensor controller-   85: battery module-   100: touch panel-   106: connection portion-   106 a: connection portion-   106 b: connection portion-   109: connection layer-   109 a: connection layer-   109 b: connection layer-   111: substrate-   112: substrate-   113: substrate-   114: substrate-   130: protective substrate-   131: polarizing plate-   132: polarizing plate-   133: backlight-   151: adhesive layer-   152: adhesive layer-   153: adhesive layer-   154: adhesive layer-   155: adhesive layer-   156: adhesive layer-   157: adhesive layer-   158: adhesive layer-   161: insulating layer-   191: substrate-   192: adhesive layer-   193: substrate-   194: insulating layer-   201: transistor-   202: transistor-   203: transistor-   204: display element-   205: capacitor-   206: connection portion-   207: wiring-   208: display element-   209: connection layer-   211: insulating layer-   212: insulating layer-   213: insulating layer-   214: insulating layer-   215: insulating layer-   216: spacer-   221: electrode-   222: EL layer-   223: electrode-   224: optical adjustment layer-   231: coloring layer-   232: light-blocking layer-   233: insulating layer-   234: insulating layer-   251: electrode-   252: electrode-   253: liquid crystal-   254: insulating layer-   255: overcoat-   261: semiconductor layer-   262: region-   263: region-   310: input device-   330: substrate-   331: electrode-   332: electrode-   333: electrode-   334: bridge electrode-   336: electrode-   337: electrode-   338: intersection portion-   341: wiring-   342: wiring-   350: FPC-   350 a: FPC-   350 b: FPC-   351: IC-   361: conductive film-   362: conductive film-   363: conductive film-   364: nanowire-   370: display panel-   371: substrate-   372: substrate-   373: FPC-   374: IC-   381: display portion-   382: driver circuit-   383: wiring-   385: connection portion-   386: connector-   387: intersection portion-   391: substrate-   392: connection layer-   393: substrate-   394: insulating layer-   3501: wiring-   3502: wiring-   3503: transistor-   3504: liquid crystal element-   3510: wiring-   3510_1: wiring-   3510_2: wiring-   3511: wiring-   3515_1: block-   3515_2: block-   3516: block

1. A display device attachable to an electronic device, wherein theelectronic device includes a housing, wherein the housing includes afirst display portion and a second display portion, wherein the firstdisplay portion is positioned on a first surface including an uppersurface of the housing, wherein the second display portion is positionedon a second surface including a first side surface of the housing,wherein the display device includes a support portion, a connectionportion, and a third display portion, wherein the third display portionis positioned on a third surface of the support portion, wherein theconnection portion has a function of connecting with the housing and afunction of reversibly changing relative positions of the supportportion and the housing between a first configuration and a secondconfiguration, wherein the first configuration is a configuration inwhich the support portion covers the first display portion such that thesecond display portion is visible, and wherein the second configurationis a configuration in which the support portion and the housing areopened such that the first display portion, the second display portion,and the third display portion are visible.
 2. The display deviceaccording to claim 1, wherein, in the first configuration, the firstdisplay portion and the third display portion are positioned to faceeach other.
 3. The display device according to claim 1, wherein, in thefirst configuration, the support portion is positioned not to cover atleast a portion of the second display portion.
 4. The display deviceaccording to claim 1, wherein the support portion includes alight-transmitting portion, and wherein, in the first configuration, thelight-transmitting portion is positioned to cover a portion of the firstside surface of the housing so as to overlap with the second displayportion.
 5. The display device according to claim 1, wherein the supportportion is flexible and has a function of allowing the third displayportion to be bent.
 6. The display device according to claim 1, whereinthe connection portion is flexible, and wherein the relative positionsof the support portion and the housing are reversibly changed betweenthe first configuration and the second configuration by bending theconnection portion.
 7. The display device according to claim 1, whereinthe connection portion includes a hinge structure with two or morerotation axes, and wherein the hinge structure enables the relativepositions of the support portion and the housing to be reversiblychanged between the first configuration and the second configuration. 8.The display device according to claim 1, wherein the connection portionincludes a reception portion supplied with power and a signal from thehousing.
 9. The display device according to claim 8, wherein thereception portion is supplied with the power and the signal wirelessly.10. The display device according to claim 1, wherein the connectionportion has a function of being magnetically attachable to anddetachable from the housing.
 11. An electronic device to which a displaydevice is attachable, wherein the electronic device includes a housing,wherein the housing includes a first display portion and a seconddisplay portion, wherein the first display portion is positioned on afirst surface including an upper surface of the housing, wherein thesecond display portion is positioned on a second surface including afirst side surface of the housing, wherein the display device includes asupport portion, a connection portion, and a third display portion,wherein the third display portion is positioned on a third surface ofthe support portion, wherein the connection portion has a function ofconnecting with the housing and a function of reversibly changingrelative positions of the support portion and the housing between afirst configuration and a second configuration, wherein the firstconfiguration is a configuration in which the support portion covers thefirst display portion such that the second display portion is visible,and wherein the second configuration is a configuration in which thesupport portion and the housing are opened such that the first displayportion, the second display portion, and the third display portion arevisible.
 12. The electronic device according to claim 11, wherein theconnection portion is attachable to a second side surface opposite tothe first side surface of the housing.
 13. The electronic deviceaccording to claim 11, wherein the first display portion and the seconddisplay portion are constituted by one display panel, and wherein thesecond display portion includes a curved portion.
 14. The electronicdevice according to claim 11, wherein the housing includes a supportmechanism, and wherein, in the second configuration, the supportmechanism has a function of supporting the support portion such that thefirst surface and the third surface are at a predetermined angle. 15.The electronic device according to claim 14, wherein the supportmechanism includes a lock mechanism such that the relative positions ofthe housing and the support portion include a plurality of stablepositions.
 16. The electronic device according to claim 11, wherein thehousing includes a transmission portion for supplying power and a signalto the connection portion.
 17. The electronic device according to claim16, wherein the transmission portion supplies the power and the signalfrom the housing wirelessly.
 18. The electronic device according toclaim 11, wherein the housing has a function of being magneticallyattachable to and detachable from the connection portion.
 19. A systemcomprising an electronic device and a display device attachable to theelectronic device, wherein the electronic device includes a housing,wherein the housing includes a first display portion and a seconddisplay portion, wherein the first display portion is positioned on afirst surface including an upper surface of the housing, wherein thesecond display portion is positioned on a second surface including afirst side surface of the housing, wherein the display device includes asupport portion, a connection portion, and a third display portion,wherein the third display portion is positioned on a third surface ofthe support portion, wherein the connection portion has a function ofconnecting with the housing and a function of reversibly changingrelative positions of the support portion and the housing between afirst configuration and a second configuration, wherein the firstconfiguration is a configuration in which the support portion covers thefirst display portion such that the second display portion is visible,and wherein the second configuration is a configuration in which thesupport portion and the housing are opened such that the first displayportion, the second display portion, and the third display portion arevisible.
 20. The system according to claim 19, wherein the connectionportion includes a reception portion supplied with power and a signalfrom the housing, and wherein the housing includes a transmissionportion for supplying power and a signal to the connection portion. 21.The system according to claim 20, wherein the reception portion issupplied with the power and the signal from the housing wirelessly, andwherein the transmission portion supplies the power and the signal fromthe housing wirelessly.
 22. The system according to claim 19, whereinthe connection portion has a function of being magnetically attachableto and detachable from the housing.